RIO TINTO AMERICA, INC. has sponsored the creation of one or more 401k plans.
Submission information for form 5500 for 401k plan RIO TINTO AMERICA MASTER RETIREMENT TRUST
| Measure | Date | Value |
|---|
| 2021 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2021 401k financial data |
|---|
| Total transfer of assets from this plan | 2021-01-01 | $988,207,003 |
| Total liabilities at end of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2021-01-01 | $0 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2021-01-01 | $236,024,454 |
| Total income from all sources (including contributions) | 2021-01-01 | $0 |
| Total loss/gain on sale of assets | 2021-01-01 | $0 |
| Total of all expenses incurred | 2021-01-01 | $0 |
| Value of total assets at end of year | 2021-01-01 | $0 |
| Value of total assets at beginning of year | 2021-01-01 | $1,224,231,457 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2021-01-01 | $0 |
| Total interest from all sources | 2021-01-01 | $0 |
| Total dividends received (eg from common stock, registered investment company shares) | 2021-01-01 | $0 |
| Value of any plan assets that reverted to the employer resulting from resoluton to terminate the plan | 2021-01-01 | $0 |
| Administrative expenses professional fees incurred | 2021-01-01 | $0 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2021-01-01 | $0 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2021-01-01 | $50,994 |
| Were there any nonexempt tranactions with any party-in-interest | 2021-01-01 | No |
| Assets. Other investments not covered elsewhere at end of year | 2021-01-01 | $0 |
| Assets. Other investments not covered elsewhere at beginning of year | 2021-01-01 | $25,728,843 |
| Value of other receiveables (less allowance for doubtful accounts) at end of year | 2021-01-01 | $0 |
| Value of other receiveables (less allowance for doubtful accounts) at beginning of year | 2021-01-01 | $80,840,642 |
| Assets. Loans (other than to participants) at end of year | 2021-01-01 | $0 |
| Assets. Loans (other than to participants) at beginning of year | 2021-01-01 | $61,758,120 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at end of year | 2021-01-01 | $0 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at beginning of year | 2021-01-01 | $236,024,454 |
| Other income not declared elsewhere | 2021-01-01 | $0 |
| Administrative expenses (other) incurred | 2021-01-01 | $0 |
| Total non interest bearing cash at end of year | 2021-01-01 | $0 |
| Total non interest bearing cash at beginning of year | 2021-01-01 | $3,169,572 |
| Value of net income/loss | 2021-01-01 | $0 |
| Value of net assets at end of year (total assets less liabilities) | 2021-01-01 | $0 |
| Value of net assets at beginning of year (total assets less liabilities) | 2021-01-01 | $988,207,003 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2021-01-01 | No |
| Were any leases to which the plan was party in default or uncollectible | 2021-01-01 | No |
| Assets. partnership/joint venture interests at end of year | 2021-01-01 | $0 |
| Assets. partnership/joint venture interests at beginning of year | 2021-01-01 | $183,728,904 |
| Investment advisory and management fees | 2021-01-01 | $0 |
| Income. Interest from loans (other than to participants) | 2021-01-01 | $0 |
| Income. Interest from US Government securities | 2021-01-01 | $0 |
| Income. Interest from corporate debt instruments | 2021-01-01 | $0 |
| Value of interest in common/collective trusts at end of year | 2021-01-01 | $0 |
| Value of interest in common/collective trusts at beginning of year | 2021-01-01 | $48,209,305 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2021-01-01 | $0 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2021-01-01 | $25,509,469 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2021-01-01 | $25,509,469 |
| Interest earned from interest bearing cash (including money market accounts and certificates of deposit) | 2021-01-01 | $0 |
| Asset value of US Government securities at end of year | 2021-01-01 | $0 |
| Asset value of US Government securities at beginning of year | 2021-01-01 | $374,204,964 |
| Net investment gain or loss from common/collective trusts | 2021-01-01 | $0 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2021-01-01 | No |
| Income. Dividends from preferred stock | 2021-01-01 | $0 |
| Income. Dividends from common stock | 2021-01-01 | $0 |
| Asset. Corporate debt instrument debt (other) at end of year | 2021-01-01 | $0 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2021-01-01 | $421,029,707 |
| Contract administrator fees | 2021-01-01 | $0 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2021-01-01 | $0 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2021-01-01 | $937 |
| Did the plan have assets held for investment | 2021-01-01 | No |
| Aggregate proceeds on sale of assets | 2021-01-01 | $0 |
| 2020 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2020 401k financial data |
|---|
| Unrealized appreciation/depreciation of real estate assets | 2020-12-31 | $18,927,975 |
| Unrealized appreciation/depreciation of other (non real estate) assets | 2020-12-31 | $44,889,225 |
| Total unrealized appreciation/depreciation of assets | 2020-12-31 | $63,817,200 |
| Total transfer of assets from this plan | 2020-12-31 | $47,855,301 |
| Total liabilities at end of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2020-12-31 | $236,024,454 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2020-12-31 | $311,808,185 |
| Total income from all sources (including contributions) | 2020-12-31 | $151,822,516 |
| Total loss/gain on sale of assets | 2020-12-31 | $56,472,504 |
| Total of all expenses incurred | 2020-12-31 | $4,065,461 |
| Value of total assets at end of year | 2020-12-31 | $1,224,231,457 |
| Value of total assets at beginning of year | 2020-12-31 | $1,200,113,434 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2020-12-31 | $4,065,461 |
| Total interest from all sources | 2020-12-31 | $23,577,772 |
| Total dividends received (eg from common stock, registered investment company shares) | 2020-12-31 | $1,516,864 |
| Value of any plan assets that reverted to the employer resulting from resoluton to terminate the plan | 2020-12-31 | $0 |
| Total dividends received from registered investment company shares (eg mutual funds) | 2020-12-31 | $1,516,318 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2020-12-31 | $50,994 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2020-12-31 | $49,428 |
| Were there any nonexempt tranactions with any party-in-interest | 2020-12-31 | Yes |
| Amount of non-exempt transactions with any party-in-interest | 2020-12-31 | $307 |
| Assets. Other investments not covered elsewhere at end of year | 2020-12-31 | $25,728,843 |
| Assets. Other investments not covered elsewhere at beginning of year | 2020-12-31 | $21,928,313 |
| Value of other receiveables (less allowance for doubtful accounts) at end of year | 2020-12-31 | $80,840,642 |
| Value of other receiveables (less allowance for doubtful accounts) at beginning of year | 2020-12-31 | $101,192,833 |
| Assets. Loans (other than to participants) at end of year | 2020-12-31 | $61,758,120 |
| Assets. Loans (other than to participants) at beginning of year | 2020-12-31 | $39,476,479 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at end of year | 2020-12-31 | $236,024,454 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at beginning of year | 2020-12-31 | $311,808,185 |
| Other income not declared elsewhere | 2020-12-31 | $3,114,911 |
| Total non interest bearing cash at end of year | 2020-12-31 | $3,169,572 |
| Total non interest bearing cash at beginning of year | 2020-12-31 | $1,938,675 |
| Value of net income/loss | 2020-12-31 | $147,757,055 |
| Value of net assets at end of year (total assets less liabilities) | 2020-12-31 | $988,207,003 |
| Value of net assets at beginning of year (total assets less liabilities) | 2020-12-31 | $888,305,249 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2020-12-31 | No |
| Were any leases to which the plan was party in default or uncollectible | 2020-12-31 | No |
| Assets. partnership/joint venture interests at end of year | 2020-12-31 | $183,728,904 |
| Assets. partnership/joint venture interests at beginning of year | 2020-12-31 | $183,617,723 |
| Investment advisory and management fees | 2020-12-31 | $3,910,220 |
| Income. Interest from loans (other than to participants) | 2020-12-31 | $4,426 |
| Interest earned on other investments | 2020-12-31 | $2,595,701 |
| Income. Interest from US Government securities | 2020-12-31 | $4,366,212 |
| Income. Interest from corporate debt instruments | 2020-12-31 | $16,494,637 |
| Value of interest in common/collective trusts at end of year | 2020-12-31 | $48,209,305 |
| Value of interest in common/collective trusts at beginning of year | 2020-12-31 | $109,487,735 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2020-12-31 | $25,509,469 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2020-12-31 | $60,453,651 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2020-12-31 | $60,453,651 |
| Interest earned from interest bearing cash (including money market accounts and certificates of deposit) | 2020-12-31 | $116,796 |
| Asset value of US Government securities at end of year | 2020-12-31 | $374,204,964 |
| Asset value of US Government securities at beginning of year | 2020-12-31 | $373,162,184 |
| Net investment gain or loss from common/collective trusts | 2020-12-31 | $3,323,265 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2020-12-31 | Yes |
| Income. Dividends from preferred stock | 2020-12-31 | $546 |
| Asset. Corporate debt instrument debt (other) at end of year | 2020-12-31 | $421,029,707 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2020-12-31 | $308,806,394 |
| Contract administrator fees | 2020-12-31 | $155,241 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2020-12-31 | $937 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2020-12-31 | $19 |
| Did the plan have assets held for investment | 2020-12-31 | Yes |
| Aggregate proceeds on sale of assets | 2020-12-31 | $56,472,504 |
| 2019 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2019 401k financial data |
|---|
| Unrealized appreciation/depreciation of real estate assets | 2019-12-31 | $24,849,039 |
| Unrealized appreciation/depreciation of other (non real estate) assets | 2019-12-31 | $35,036,788 |
| Total unrealized appreciation/depreciation of assets | 2019-12-31 | $59,885,827 |
| Total transfer of assets to this plan | 2019-12-31 | $39,162,870 |
| Total transfer of assets from this plan | 2019-12-31 | $651,362,431 |
| Total liabilities at end of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2019-12-31 | $311,808,185 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2019-12-31 | $81,858,782 |
| Total income from all sources (including contributions) | 2019-12-31 | $185,357,034 |
| Total loss/gain on sale of assets | 2019-12-31 | $63,852,992 |
| Total of all expenses incurred | 2019-12-31 | $4,832,619 |
| Value of total assets at end of year | 2019-12-31 | $1,200,113,434 |
| Value of total assets at beginning of year | 2019-12-31 | $1,401,839,177 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2019-12-31 | $4,832,619 |
| Total interest from all sources | 2019-12-31 | $26,231,704 |
| Total dividends received (eg from common stock, registered investment company shares) | 2019-12-31 | $7,968,469 |
| Total dividends received from registered investment company shares (eg mutual funds) | 2019-12-31 | $7,952,324 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2019-12-31 | $49,428 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2019-12-31 | $44,064 |
| Were there any nonexempt tranactions with any party-in-interest | 2019-12-31 | Yes |
| Amount of non-exempt transactions with any party-in-interest | 2019-12-31 | $307 |
| Assets. Other investments not covered elsewhere at end of year | 2019-12-31 | $21,928,313 |
| Assets. Other investments not covered elsewhere at beginning of year | 2019-12-31 | $19,623,689 |
| Value of other receiveables (less allowance for doubtful accounts) at end of year | 2019-12-31 | $101,192,833 |
| Value of other receiveables (less allowance for doubtful accounts) at beginning of year | 2019-12-31 | $32,435,386 |
| Assets. Loans (other than to participants) at end of year | 2019-12-31 | $39,476,479 |
| Assets. Loans (other than to participants) at beginning of year | 2019-12-31 | $18,728,397 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at end of year | 2019-12-31 | $311,808,185 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at beginning of year | 2019-12-31 | $81,858,782 |
| Other income not declared elsewhere | 2019-12-31 | $4,070,924 |
| Total non interest bearing cash at end of year | 2019-12-31 | $1,938,675 |
| Total non interest bearing cash at beginning of year | 2019-12-31 | $2,299,939 |
| Value of net income/loss | 2019-12-31 | $180,524,415 |
| Value of net assets at end of year (total assets less liabilities) | 2019-12-31 | $888,305,249 |
| Value of net assets at beginning of year (total assets less liabilities) | 2019-12-31 | $1,319,980,395 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2019-12-31 | No |
| Were any leases to which the plan was party in default or uncollectible | 2019-12-31 | No |
| Assets. partnership/joint venture interests at end of year | 2019-12-31 | $183,617,723 |
| Assets. partnership/joint venture interests at beginning of year | 2019-12-31 | $202,548,642 |
| Investment advisory and management fees | 2019-12-31 | $4,617,112 |
| Income. Interest from loans (other than to participants) | 2019-12-31 | $967 |
| Interest earned on other investments | 2019-12-31 | $3,412,276 |
| Income. Interest from US Government securities | 2019-12-31 | $2,045,929 |
| Income. Interest from corporate debt instruments | 2019-12-31 | $19,657,121 |
| Value of interest in common/collective trusts at end of year | 2019-12-31 | $109,487,735 |
| Value of interest in common/collective trusts at beginning of year | 2019-12-31 | $302,143,541 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2019-12-31 | $60,453,651 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2019-12-31 | $56,724,618 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2019-12-31 | $56,724,618 |
| Interest earned from interest bearing cash (including money market accounts and certificates of deposit) | 2019-12-31 | $1,115,411 |
| Asset value of US Government securities at end of year | 2019-12-31 | $373,162,184 |
| Asset value of US Government securities at beginning of year | 2019-12-31 | $144,970,496 |
| Net investment gain or loss from common/collective trusts | 2019-12-31 | $23,347,118 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2019-12-31 | Yes |
| Income. Dividends from preferred stock | 2019-12-31 | $2,655 |
| Income. Dividends from common stock | 2019-12-31 | $13,490 |
| Asset. Corporate debt instrument debt (other) at end of year | 2019-12-31 | $308,806,394 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2019-12-31 | $615,912,498 |
| Contract administrator fees | 2019-12-31 | $215,507 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2019-12-31 | $19 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2019-12-31 | $6,407,907 |
| Did the plan have assets held for investment | 2019-12-31 | Yes |
| Aggregate proceeds on sale of assets | 2019-12-31 | $63,852,992 |
| 2018 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2018 401k financial data |
|---|
| Unrealized appreciation/depreciation of real estate assets | 2018-12-31 | $34,029,354 |
| Unrealized appreciation/depreciation of other (non real estate) assets | 2018-12-31 | $-61,539,543 |
| Total unrealized appreciation/depreciation of assets | 2018-12-31 | $-27,510,189 |
| Total transfer of assets to this plan | 2018-12-31 | $52,000,000 |
| Total transfer of assets from this plan | 2018-12-31 | $383,050,608 |
| Total liabilities at end of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2018-12-31 | $81,858,782 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2018-12-31 | $71,332,718 |
| Total income from all sources (including contributions) | 2018-12-31 | $-29,193,052 |
| Total loss/gain on sale of assets | 2018-12-31 | $-28,309,910 |
| Total of all expenses incurred | 2018-12-31 | $4,137,647 |
| Benefit payments and payments to participlants,beneficiaries,insurance carriers and others | 2018-12-31 | $0 |
| Total contributions o plan (from employers,participants, others, non cash contrinutions) | 2018-12-31 | $0 |
| Value of total assets at end of year | 2018-12-31 | $1,401,839,177 |
| Value of total assets at beginning of year | 2018-12-31 | $1,755,694,420 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2018-12-31 | $4,137,647 |
| Total interest from all sources | 2018-12-31 | $38,270,382 |
| Total dividends received (eg from common stock, registered investment company shares) | 2018-12-31 | $7,316,246 |
| Total dividends received from registered investment company shares (eg mutual funds) | 2018-12-31 | $6,763,191 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2018-12-31 | $44,064 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2018-12-31 | $98,856 |
| Were there any nonexempt tranactions with any party-in-interest | 2018-12-31 | No |
| Assets. Other investments not covered elsewhere at end of year | 2018-12-31 | $19,623,689 |
| Assets. Other investments not covered elsewhere at beginning of year | 2018-12-31 | $102,286,219 |
| Value of other receiveables (less allowance for doubtful accounts) at end of year | 2018-12-31 | $32,435,386 |
| Value of other receiveables (less allowance for doubtful accounts) at beginning of year | 2018-12-31 | $18,737,288 |
| Assets. Loans (other than to participants) at end of year | 2018-12-31 | $18,728,397 |
| Assets. Loans (other than to participants) at beginning of year | 2018-12-31 | $8,458,425 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at end of year | 2018-12-31 | $81,858,782 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at beginning of year | 2018-12-31 | $71,332,718 |
| Other income not declared elsewhere | 2018-12-31 | $4,820,803 |
| Total non interest bearing cash at end of year | 2018-12-31 | $2,299,939 |
| Total non interest bearing cash at beginning of year | 2018-12-31 | $361,966 |
| Value of net income/loss | 2018-12-31 | $-33,330,699 |
| Value of net assets at end of year (total assets less liabilities) | 2018-12-31 | $1,319,980,395 |
| Value of net assets at beginning of year (total assets less liabilities) | 2018-12-31 | $1,684,361,702 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2018-12-31 | No |
| Were any leases to which the plan was party in default or uncollectible | 2018-12-31 | No |
| Assets. partnership/joint venture interests at end of year | 2018-12-31 | $202,548,642 |
| Assets. partnership/joint venture interests at beginning of year | 2018-12-31 | $206,326,759 |
| Investment advisory and management fees | 2018-12-31 | $3,963,976 |
| Income. Interest from loans (other than to participants) | 2018-12-31 | $23,317 |
| Interest earned on other investments | 2018-12-31 | $5,825,419 |
| Income. Interest from US Government securities | 2018-12-31 | $1,674,012 |
| Income. Interest from corporate debt instruments | 2018-12-31 | $29,627,071 |
| Value of interest in common/collective trusts at end of year | 2018-12-31 | $302,143,541 |
| Value of interest in common/collective trusts at beginning of year | 2018-12-31 | $480,392,518 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2018-12-31 | $56,724,618 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2018-12-31 | $46,370,308 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2018-12-31 | $46,370,308 |
| Interest earned from interest bearing cash (including money market accounts and certificates of deposit) | 2018-12-31 | $1,120,563 |
| Asset value of US Government securities at end of year | 2018-12-31 | $144,970,496 |
| Asset value of US Government securities at beginning of year | 2018-12-31 | $165,872,304 |
| Net investment gain or loss from common/collective trusts | 2018-12-31 | $-23,780,384 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2018-12-31 | No |
| Income. Dividends from preferred stock | 2018-12-31 | $3,466 |
| Income. Dividends from common stock | 2018-12-31 | $549,589 |
| Asset. Corporate debt instrument debt (other) at end of year | 2018-12-31 | $615,912,498 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2018-12-31 | $644,064,824 |
| Contract administrator fees | 2018-12-31 | $173,671 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2018-12-31 | $6,407,907 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2018-12-31 | $82,724,953 |
| Did the plan have assets held for investment | 2018-12-31 | Yes |
| Aggregate proceeds on sale of assets | 2018-12-31 | $-28,309,910 |
| 2017 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2017 401k financial data |
|---|
| Unrealized appreciation/depreciation of real estate assets | 2017-12-31 | $30,980,528 |
| Unrealized appreciation/depreciation of other (non real estate) assets | 2017-12-31 | $142,702,715 |
| Total unrealized appreciation/depreciation of assets | 2017-12-31 | $173,683,243 |
| Total transfer of assets to this plan | 2017-12-31 | $150,000,000 |
| Total transfer of assets from this plan | 2017-12-31 | $376,845,974 |
| Total liabilities at end of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2017-12-31 | $71,332,718 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2017-12-31 | $89,558,143 |
| Total income from all sources (including contributions) | 2017-12-31 | $277,130,260 |
| Total loss/gain on sale of assets | 2017-12-31 | $1,362,637 |
| Total of all expenses incurred | 2017-12-31 | $4,708,415 |
| Value of total assets at end of year | 2017-12-31 | $1,755,694,420 |
| Value of total assets at beginning of year | 2017-12-31 | $1,728,343,974 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2017-12-31 | $4,708,415 |
| Total interest from all sources | 2017-12-31 | $37,652,218 |
| Total dividends received (eg from common stock, registered investment company shares) | 2017-12-31 | $10,981,838 |
| Total dividends received from registered investment company shares (eg mutual funds) | 2017-12-31 | $9,742,019 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2017-12-31 | $98,856 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2017-12-31 | $297,505 |
| Were there any nonexempt tranactions with any party-in-interest | 2017-12-31 | No |
| Assets. Other investments not covered elsewhere at end of year | 2017-12-31 | $102,286,219 |
| Assets. Other investments not covered elsewhere at beginning of year | 2017-12-31 | $86,151,317 |
| Value of other receiveables (less allowance for doubtful accounts) at end of year | 2017-12-31 | $18,737,288 |
| Value of other receiveables (less allowance for doubtful accounts) at beginning of year | 2017-12-31 | $31,071,751 |
| Assets. Loans (other than to participants) at end of year | 2017-12-31 | $8,458,425 |
| Assets. Loans (other than to participants) at beginning of year | 2017-12-31 | $18,970,431 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at end of year | 2017-12-31 | $71,332,718 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at beginning of year | 2017-12-31 | $89,558,143 |
| Other income not declared elsewhere | 2017-12-31 | $8,159,307 |
| Total non interest bearing cash at end of year | 2017-12-31 | $361,966 |
| Total non interest bearing cash at beginning of year | 2017-12-31 | $1,816,315 |
| Value of net income/loss | 2017-12-31 | $272,421,845 |
| Value of net assets at end of year (total assets less liabilities) | 2017-12-31 | $1,684,361,702 |
| Value of net assets at beginning of year (total assets less liabilities) | 2017-12-31 | $1,638,785,831 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2017-12-31 | No |
| Were any leases to which the plan was party in default or uncollectible | 2017-12-31 | No |
| Assets. partnership/joint venture interests at end of year | 2017-12-31 | $206,326,759 |
| Assets. partnership/joint venture interests at beginning of year | 2017-12-31 | $211,071,393 |
| Investment advisory and management fees | 2017-12-31 | $4,443,071 |
| Income. Interest from loans (other than to participants) | 2017-12-31 | $51,915 |
| Interest earned on other investments | 2017-12-31 | $7,846,793 |
| Income. Interest from US Government securities | 2017-12-31 | $1,845,038 |
| Income. Interest from corporate debt instruments | 2017-12-31 | $27,431,193 |
| Value of interest in common/collective trusts at end of year | 2017-12-31 | $480,392,518 |
| Value of interest in common/collective trusts at beginning of year | 2017-12-31 | $608,111,933 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2017-12-31 | $46,370,308 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2017-12-31 | $59,108,969 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2017-12-31 | $59,108,969 |
| Interest earned from interest bearing cash (including money market accounts and certificates of deposit) | 2017-12-31 | $477,279 |
| Asset value of US Government securities at end of year | 2017-12-31 | $165,872,304 |
| Asset value of US Government securities at beginning of year | 2017-12-31 | $111,698,760 |
| Net investment gain or loss from common/collective trusts | 2017-12-31 | $45,291,017 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2017-12-31 | No |
| Income. Dividends from preferred stock | 2017-12-31 | $11,135 |
| Income. Dividends from common stock | 2017-12-31 | $1,228,684 |
| Asset. Corporate debt instrument debt (other) at end of year | 2017-12-31 | $644,064,824 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2017-12-31 | $447,676,156 |
| Contract administrator fees | 2017-12-31 | $265,344 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2017-12-31 | $82,724,953 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2017-12-31 | $152,369,444 |
| Did the plan have assets held for investment | 2017-12-31 | Yes |
| Aggregate proceeds on sale of assets | 2017-12-31 | $1,362,637 |
| 2016 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2016 401k financial data |
|---|
| Unrealized appreciation/depreciation of other (non real estate) assets | 2016-12-31 | $100,354,850 |
| Total unrealized appreciation/depreciation of assets | 2016-12-31 | $100,354,850 |
| Total transfer of assets to this plan | 2016-12-31 | $100,200,000 |
| Total transfer of assets from this plan | 2016-12-31 | $132,808,768 |
| Total liabilities at end of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2016-12-31 | $89,558,143 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2016-12-31 | $102,372,966 |
| Total income from all sources (including contributions) | 2016-12-31 | $131,689,029 |
| Total loss/gain on sale of assets | 2016-12-31 | $-26,999,207 |
| Total of all expenses incurred | 2016-12-31 | $4,292,466 |
| Value of total assets at end of year | 2016-12-31 | $1,728,343,974 |
| Value of total assets at beginning of year | 2016-12-31 | $1,646,371,002 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2016-12-31 | $4,292,466 |
| Total interest from all sources | 2016-12-31 | $29,848,629 |
| Total dividends received (eg from common stock, registered investment company shares) | 2016-12-31 | $12,106,710 |
| Total dividends received from registered investment company shares (eg mutual funds) | 2016-12-31 | $9,805,060 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2016-12-31 | $297,505 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2016-12-31 | $1,022,636 |
| Were there any nonexempt tranactions with any party-in-interest | 2016-12-31 | No |
| Assets. Other investments not covered elsewhere at end of year | 2016-12-31 | $86,151,317 |
| Assets. Other investments not covered elsewhere at beginning of year | 2016-12-31 | $86,919,045 |
| Value of other receiveables (less allowance for doubtful accounts) at end of year | 2016-12-31 | $31,071,751 |
| Value of other receiveables (less allowance for doubtful accounts) at beginning of year | 2016-12-31 | $18,137,496 |
| Assets. Loans (other than to participants) at end of year | 2016-12-31 | $18,970,431 |
| Assets. Loans (other than to participants) at beginning of year | 2016-12-31 | $8,442,634 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at end of year | 2016-12-31 | $89,558,143 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at beginning of year | 2016-12-31 | $102,372,966 |
| Other income not declared elsewhere | 2016-12-31 | $346,763 |
| Total non interest bearing cash at end of year | 2016-12-31 | $1,816,315 |
| Total non interest bearing cash at beginning of year | 2016-12-31 | $2,409,522 |
| Value of net income/loss | 2016-12-31 | $127,396,563 |
| Value of net assets at end of year (total assets less liabilities) | 2016-12-31 | $1,638,785,831 |
| Value of net assets at beginning of year (total assets less liabilities) | 2016-12-31 | $1,543,998,036 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2016-12-31 | No |
| Were any leases to which the plan was party in default or uncollectible | 2016-12-31 | No |
| Assets. partnership/joint venture interests at end of year | 2016-12-31 | $211,071,393 |
| Assets. partnership/joint venture interests at beginning of year | 2016-12-31 | $217,272,858 |
| Investment advisory and management fees | 2016-12-31 | $4,001,036 |
| Income. Interest from loans (other than to participants) | 2016-12-31 | $62,991 |
| Interest earned on other investments | 2016-12-31 | $7,275,786 |
| Income. Interest from US Government securities | 2016-12-31 | $570,103 |
| Income. Interest from corporate debt instruments | 2016-12-31 | $21,722,405 |
| Value of interest in common/collective trusts at end of year | 2016-12-31 | $608,111,933 |
| Value of interest in common/collective trusts at beginning of year | 2016-12-31 | $504,777,027 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2016-12-31 | $59,108,969 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2016-12-31 | $57,951,335 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2016-12-31 | $57,951,335 |
| Interest earned from interest bearing cash (including money market accounts and certificates of deposit) | 2016-12-31 | $217,344 |
| Asset value of US Government securities at end of year | 2016-12-31 | $111,698,760 |
| Asset value of US Government securities at beginning of year | 2016-12-31 | $160,540,030 |
| Net investment gain or loss from common/collective trusts | 2016-12-31 | $16,031,284 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2016-12-31 | No |
| Income. Dividends from preferred stock | 2016-12-31 | $22,542 |
| Income. Dividends from common stock | 2016-12-31 | $2,279,108 |
| Asset. Corporate debt instrument debt (other) at end of year | 2016-12-31 | $447,676,156 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2016-12-31 | $402,096,415 |
| Contract administrator fees | 2016-12-31 | $291,430 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2016-12-31 | $152,369,444 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2016-12-31 | $186,802,004 |
| Did the plan have assets held for investment | 2016-12-31 | No |
| Aggregate proceeds on sale of assets | 2016-12-31 | $-26,999,207 |
| 2015 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2015 401k financial data |
|---|
| Unrealized appreciation/depreciation of real estate assets | 2015-12-31 | $26,223,029 |
| Unrealized appreciation/depreciation of other (non real estate) assets | 2015-12-31 | $-45,334,757 |
| Total unrealized appreciation/depreciation of assets | 2015-12-31 | $-19,111,728 |
| Total transfer of assets to this plan | 2015-12-31 | $9,555,000 |
| Total transfer of assets from this plan | 2015-12-31 | $182,058,750 |
| Total liabilities at end of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2015-12-31 | $102,372,966 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2015-12-31 | $40,917,273 |
| Total income from all sources (including contributions) | 2015-12-31 | $-8,021,251 |
| Total loss/gain on sale of assets | 2015-12-31 | $-36,645,968 |
| Total of all expenses incurred | 2015-12-31 | $4,664,348 |
| Value of total assets at end of year | 2015-12-31 | $1,646,371,002 |
| Value of total assets at beginning of year | 2015-12-31 | $1,770,104,658 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2015-12-31 | $4,664,348 |
| Total interest from all sources | 2015-12-31 | $29,848,822 |
| Total dividends received (eg from common stock, registered investment company shares) | 2015-12-31 | $14,314,544 |
| Total dividends received from registered investment company shares (eg mutual funds) | 2015-12-31 | $11,709,657 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2015-12-31 | $1,022,636 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2015-12-31 | $1,188,681 |
| Were there any nonexempt tranactions with any party-in-interest | 2015-12-31 | No |
| Assets. Other investments not covered elsewhere at end of year | 2015-12-31 | $86,919,045 |
| Assets. Other investments not covered elsewhere at beginning of year | 2015-12-31 | $308,426 |
| Value of other receiveables (less allowance for doubtful accounts) at end of year | 2015-12-31 | $18,137,496 |
| Value of other receiveables (less allowance for doubtful accounts) at beginning of year | 2015-12-31 | $13,710,594 |
| Assets. Loans (other than to participants) at end of year | 2015-12-31 | $8,442,634 |
| Assets. Loans (other than to participants) at beginning of year | 2015-12-31 | $5,671,315 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at end of year | 2015-12-31 | $102,372,966 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at beginning of year | 2015-12-31 | $40,917,273 |
| Other income not declared elsewhere | 2015-12-31 | $5,126,433 |
| Total non interest bearing cash at end of year | 2015-12-31 | $2,409,522 |
| Total non interest bearing cash at beginning of year | 2015-12-31 | $4,423,654 |
| Value of net income/loss | 2015-12-31 | $-12,685,599 |
| Value of net assets at end of year (total assets less liabilities) | 2015-12-31 | $1,543,998,036 |
| Value of net assets at beginning of year (total assets less liabilities) | 2015-12-31 | $1,729,187,385 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2015-12-31 | No |
| Were any leases to which the plan was party in default or uncollectible | 2015-12-31 | No |
| Assets. partnership/joint venture interests at end of year | 2015-12-31 | $217,272,858 |
| Assets. partnership/joint venture interests at beginning of year | 2015-12-31 | $236,038,840 |
| Investment advisory and management fees | 2015-12-31 | $4,373,679 |
| Income. Interest from loans (other than to participants) | 2015-12-31 | $109,278 |
| Interest earned on other investments | 2015-12-31 | $8,768,513 |
| Income. Interest from US Government securities | 2015-12-31 | $516,217 |
| Income. Interest from corporate debt instruments | 2015-12-31 | $20,409,927 |
| Value of interest in common/collective trusts at end of year | 2015-12-31 | $504,777,027 |
| Value of interest in common/collective trusts at beginning of year | 2015-12-31 | $460,987,387 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2015-12-31 | $57,951,335 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2015-12-31 | $60,299,138 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2015-12-31 | $60,299,138 |
| Interest earned from interest bearing cash (including money market accounts and certificates of deposit) | 2015-12-31 | $44,887 |
| Asset value of US Government securities at end of year | 2015-12-31 | $160,540,030 |
| Net investment gain or loss from common/collective trusts | 2015-12-31 | $-1,553,354 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2015-12-31 | Yes |
| Income. Dividends from preferred stock | 2015-12-31 | $72,179 |
| Income. Dividends from common stock | 2015-12-31 | $2,532,708 |
| Asset. Corporate debt instrument debt (other) at end of year | 2015-12-31 | $402,096,415 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2015-12-31 | $729,586,675 |
| Contract administrator fees | 2015-12-31 | $290,669 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2015-12-31 | $186,802,004 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2015-12-31 | $257,889,948 |
| Did the plan have assets held for investment | 2015-12-31 | Yes |
| Aggregate proceeds on sale of assets | 2015-12-31 | $-36,645,968 |
| 2014 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2014 401k financial data |
|---|
| Unrealized appreciation/depreciation of other (non real estate) assets | 2014-12-31 | $103,352,587 |
| Total unrealized appreciation/depreciation of assets | 2014-12-31 | $103,352,587 |
| Total transfer of assets to this plan | 2014-12-31 | $17,709,960 |
| Total transfer of assets from this plan | 2014-12-31 | $195,735,303 |
| Total liabilities at end of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2014-12-31 | $40,917,273 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2014-12-31 | $33,022,359 |
| Total income from all sources (including contributions) | 2014-12-31 | $157,873,544 |
| Total loss/gain on sale of assets | 2014-12-31 | $3,093,015 |
| Total of all expenses incurred | 2014-12-31 | $5,792,744 |
| Total contributions o plan (from employers,participants, others, non cash contrinutions) | 2014-12-31 | $0 |
| Value of total assets at end of year | 2014-12-31 | $1,770,104,658 |
| Value of total assets at beginning of year | 2014-12-31 | $1,788,154,287 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2014-12-31 | $5,792,744 |
| Total interest from all sources | 2014-12-31 | $44,278,130 |
| Total dividends received (eg from common stock, registered investment company shares) | 2014-12-31 | $2,656,330 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2014-12-31 | $1,188,681 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2014-12-31 | $3,666,664 |
| Were there any nonexempt tranactions with any party-in-interest | 2014-12-31 | No |
| Assets. Other investments not covered elsewhere at end of year | 2014-12-31 | $308,426 |
| Assets. Other investments not covered elsewhere at beginning of year | 2014-12-31 | $1,343,000 |
| Value of other receiveables (less allowance for doubtful accounts) at end of year | 2014-12-31 | $13,710,594 |
| Value of other receiveables (less allowance for doubtful accounts) at beginning of year | 2014-12-31 | $18,004,471 |
| Assets. Loans (other than to participants) at end of year | 2014-12-31 | $5,671,315 |
| Assets. Loans (other than to participants) at beginning of year | 2014-12-31 | $3,278,170 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at end of year | 2014-12-31 | $40,917,273 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at beginning of year | 2014-12-31 | $33,022,359 |
| Other income not declared elsewhere | 2014-12-31 | $3,186,179 |
| Total non interest bearing cash at end of year | 2014-12-31 | $4,423,654 |
| Total non interest bearing cash at beginning of year | 2014-12-31 | $1,150,506 |
| Value of net income/loss | 2014-12-31 | $152,080,800 |
| Value of net assets at end of year (total assets less liabilities) | 2014-12-31 | $1,729,187,385 |
| Value of net assets at beginning of year (total assets less liabilities) | 2014-12-31 | $1,755,131,928 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2014-12-31 | No |
| Were any leases to which the plan was party in default or uncollectible | 2014-12-31 | No |
| Assets. partnership/joint venture interests at end of year | 2014-12-31 | $236,038,840 |
| Assets. partnership/joint venture interests at beginning of year | 2014-12-31 | $211,546,350 |
| Investment advisory and management fees | 2014-12-31 | $5,792,744 |
| Income. Interest from loans (other than to participants) | 2014-12-31 | $164,103 |
| Interest earned on other investments | 2014-12-31 | $23,539,126 |
| Income. Interest from US Government securities | 2014-12-31 | $626,200 |
| Income. Interest from corporate debt instruments | 2014-12-31 | $19,948,701 |
| Value of interest in common/collective trusts at end of year | 2014-12-31 | $460,987,387 |
| Value of interest in common/collective trusts at beginning of year | 2014-12-31 | $521,229,367 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2014-12-31 | $60,299,138 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2014-12-31 | $63,058,357 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2014-12-31 | $63,058,357 |
| Asset value of US Government securities at end of year | 2014-12-31 | $0 |
| Asset value of US Government securities at beginning of year | 2014-12-31 | $88,236,220 |
| Net investment gain or loss from common/collective trusts | 2014-12-31 | $1,307,303 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2014-12-31 | Yes |
| Income. Dividends from preferred stock | 2014-12-31 | $247,542 |
| Income. Dividends from common stock | 2014-12-31 | $2,408,788 |
| Asset. Corporate debt instrument debt (other) at end of year | 2014-12-31 | $729,586,675 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2014-12-31 | $599,863,532 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2014-12-31 | $257,889,948 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2014-12-31 | $276,777,650 |
| Did the plan have assets held for investment | 2014-12-31 | Yes |
| Aggregate proceeds on sale of assets | 2014-12-31 | $3,093,015 |
| 2013 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2013 401k financial data |
|---|
| Unrealized appreciation/depreciation of other (non real estate) assets | 2013-12-31 | $16,352,263 |
| Total unrealized appreciation/depreciation of assets | 2013-12-31 | $16,352,263 |
| Total transfer of assets to this plan | 2013-12-31 | $155,821,448 |
| Total transfer of assets from this plan | 2013-12-31 | $412,874,946 |
| Total liabilities at end of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2013-12-31 | $0 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2013-12-31 | $0 |
| Total income from all sources (including contributions) | 2013-12-31 | $203,554,780 |
| Total of all expenses incurred | 2013-12-31 | $9,107,814 |
| Value of total assets at end of year | 2013-12-31 | $1,770,149,816 |
| Value of total assets at beginning of year | 2013-12-31 | $1,832,756,348 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2013-12-31 | $9,107,814 |
| Total interest from all sources | 2013-12-31 | $44,600,535 |
| Total dividends received (eg from common stock, registered investment company shares) | 2013-12-31 | $3,253,594 |
| Total dividends received from registered investment company shares (eg mutual funds) | 2013-12-31 | $1,914,783 |
| Administrative expenses professional fees incurred | 2013-12-31 | $4,608,421 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2013-12-31 | $3,666,664 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2013-12-31 | $2,632,323 |
| Were there any nonexempt tranactions with any party-in-interest | 2013-12-31 | No |
| Assets. Other investments not covered elsewhere at end of year | 2013-12-31 | $1,343,000 |
| Assets. Other investments not covered elsewhere at beginning of year | 2013-12-31 | $748,000 |
| Assets. Loans (other than to participants) at end of year | 2013-12-31 | $3,278,170 |
| Assets. Loans (other than to participants) at beginning of year | 2013-12-31 | $5,031,140 |
| Other income not declared elsewhere | 2013-12-31 | $22,026,814 |
| Administrative expenses (other) incurred | 2013-12-31 | $5,623 |
| Total non interest bearing cash at end of year | 2013-12-31 | $1,150,506 |
| Total non interest bearing cash at beginning of year | 2013-12-31 | $6,993,144 |
| Value of net income/loss | 2013-12-31 | $194,446,966 |
| Value of net assets at end of year (total assets less liabilities) | 2013-12-31 | $1,770,149,816 |
| Value of net assets at beginning of year (total assets less liabilities) | 2013-12-31 | $1,832,756,348 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2013-12-31 | No |
| Were any leases to which the plan was party in default or uncollectible | 2013-12-31 | No |
| Assets. partnership/joint venture interests at end of year | 2013-12-31 | $211,546,350 |
| Assets. partnership/joint venture interests at beginning of year | 2013-12-31 | $167,697,803 |
| Investment advisory and management fees | 2013-12-31 | $4,493,770 |
| Value of interest in registered invesment companies (eg mutual funds) at end of year | 2013-12-31 | $0 |
| Value of interest in registered invesment companies (eg mutual funds) at beginning of year | 2013-12-31 | $8,967,530 |
| Income. Interest from loans (other than to participants) | 2013-12-31 | $1,150,546 |
| Interest earned on other investments | 2013-12-31 | $13,541,975 |
| Income. Interest from US Government securities | 2013-12-31 | $8,109,188 |
| Income. Interest from corporate debt instruments | 2013-12-31 | $21,706,537 |
| Value of interest in common/collective trusts at end of year | 2013-12-31 | $521,229,367 |
| Value of interest in common/collective trusts at beginning of year | 2013-12-31 | $661,513,837 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2013-12-31 | $63,058,357 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2013-12-31 | $36,138,140 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2013-12-31 | $36,138,140 |
| Interest earned from interest bearing cash (including money market accounts and certificates of deposit) | 2013-12-31 | $92,289 |
| Asset value of US Government securities at end of year | 2013-12-31 | $88,236,220 |
| Asset value of US Government securities at beginning of year | 2013-12-31 | $90,422,384 |
| Net investment gain/loss from registered investment companies (e.g. mutual funds) | 2013-12-31 | $356,107 |
| Net investment gain or loss from common/collective trusts | 2013-12-31 | $116,965,467 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2013-12-31 | No |
| Income. Dividends from preferred stock | 2013-12-31 | $94,616 |
| Income. Dividends from common stock | 2013-12-31 | $1,244,195 |
| Asset. Corporate debt instrument debt (other) at end of year | 2013-12-31 | $599,863,532 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2013-12-31 | $622,791,026 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2013-12-31 | $276,777,650 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2013-12-31 | $229,821,021 |
| Did the plan have assets held for investment | 2013-12-31 | Yes |
| 2012 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2012 401k financial data |
|---|
| Unrealized appreciation/depreciation of other (non real estate) assets | 2012-12-31 | $99,721,164 |
| Total unrealized appreciation/depreciation of assets | 2012-12-31 | $99,721,164 |
| Total transfer of assets to this plan | 2012-12-31 | $14,520,000 |
| Total transfer of assets from this plan | 2012-12-31 | $100,670,536 |
| Total liabilities at end of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2012-12-31 | $0 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2012-12-31 | $0 |
| Total income from all sources (including contributions) | 2012-12-31 | $267,270,922 |
| Total of all expenses incurred | 2012-12-31 | $7,455,366 |
| Value of total assets at end of year | 2012-12-31 | $1,832,756,348 |
| Value of total assets at beginning of year | 2012-12-31 | $1,659,091,328 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2012-12-31 | $7,455,366 |
| Total interest from all sources | 2012-12-31 | $35,110,945 |
| Total dividends received (eg from common stock, registered investment company shares) | 2012-12-31 | $13,324,626 |
| Total dividends received from registered investment company shares (eg mutual funds) | 2012-12-31 | $7,841,719 |
| Administrative expenses professional fees incurred | 2012-12-31 | $2,876,946 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2012-12-31 | $2,632,323 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2012-12-31 | $2,269,649 |
| Were there any nonexempt tranactions with any party-in-interest | 2012-12-31 | No |
| Assets. Other investments not covered elsewhere at end of year | 2012-12-31 | $748,000 |
| Assets. Other investments not covered elsewhere at beginning of year | 2012-12-31 | $0 |
| Assets. Loans (other than to participants) at end of year | 2012-12-31 | $5,031,140 |
| Assets. Loans (other than to participants) at beginning of year | 2012-12-31 | $6,640,910 |
| Other income not declared elsewhere | 2012-12-31 | $13,779,878 |
| Administrative expenses (other) incurred | 2012-12-31 | $50,395 |
| Total non interest bearing cash at end of year | 2012-12-31 | $6,993,144 |
| Total non interest bearing cash at beginning of year | 2012-12-31 | $1,614,946 |
| Value of net income/loss | 2012-12-31 | $259,815,556 |
| Value of net assets at end of year (total assets less liabilities) | 2012-12-31 | $1,832,756,348 |
| Value of net assets at beginning of year (total assets less liabilities) | 2012-12-31 | $1,659,091,328 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2012-12-31 | No |
| Were any leases to which the plan was party in default or uncollectible | 2012-12-31 | No |
| Assets. partnership/joint venture interests at end of year | 2012-12-31 | $167,697,803 |
| Assets. partnership/joint venture interests at beginning of year | 2012-12-31 | $124,538,963 |
| Investment advisory and management fees | 2012-12-31 | $4,528,025 |
| Value of interest in registered invesment companies (eg mutual funds) at end of year | 2012-12-31 | $8,967,530 |
| Value of interest in registered invesment companies (eg mutual funds) at beginning of year | 2012-12-31 | $10,810,495 |
| Income. Interest from loans (other than to participants) | 2012-12-31 | $905,746 |
| Interest earned on other investments | 2012-12-31 | $10,660,669 |
| Income. Interest from US Government securities | 2012-12-31 | $6,383,808 |
| Income. Interest from corporate debt instruments | 2012-12-31 | $17,088,069 |
| Value of interest in common/collective trusts at end of year | 2012-12-31 | $661,513,837 |
| Value of interest in common/collective trusts at beginning of year | 2012-12-31 | $697,430,304 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2012-12-31 | $36,138,140 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2012-12-31 | $51,910,484 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2012-12-31 | $51,910,484 |
| Interest earned from interest bearing cash (including money market accounts and certificates of deposit) | 2012-12-31 | $72,653 |
| Asset value of US Government securities at end of year | 2012-12-31 | $90,422,384 |
| Asset value of US Government securities at beginning of year | 2012-12-31 | $207,388,365 |
| Net investment gain/loss from registered investment companies (e.g. mutual funds) | 2012-12-31 | $3,130,788 |
| Net investment gain or loss from common/collective trusts | 2012-12-31 | $102,203,521 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2012-12-31 | No |
| Income. Dividends from preferred stock | 2012-12-31 | $387,485 |
| Income. Dividends from common stock | 2012-12-31 | $5,095,422 |
| Asset. Corporate debt instrument debt (other) at end of year | 2012-12-31 | $622,791,026 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2012-12-31 | $270,499,499 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2012-12-31 | $229,821,021 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2012-12-31 | $285,987,713 |
| Did the plan have assets held for investment | 2012-12-31 | Yes |
| 2011 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2011 401k financial data |
|---|
| Unrealized appreciation/depreciation of other (non real estate) assets | 2011-12-31 | $11,710,548 |
| Total unrealized appreciation/depreciation of assets | 2011-12-31 | $11,710,548 |
| Total transfer of assets to this plan | 2011-12-31 | $37,581,648 |
| Total transfer of assets from this plan | 2011-12-31 | $223,426,615 |
| Total liabilities at end of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2011-12-31 | $0 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2011-12-31 | $0 |
| Total income from all sources (including contributions) | 2011-12-31 | $7,780,238 |
| Total loss/gain on sale of assets | 2011-12-31 | $0 |
| Total of all expenses incurred | 2011-12-31 | $6,920,035 |
| Benefit payments and payments to participlants,beneficiaries,insurance carriers and others | 2011-12-31 | $0 |
| Total contributions o plan (from employers,participants, others, non cash contrinutions) | 2011-12-31 | $0 |
| Value of total assets at end of year | 2011-12-31 | $1,659,091,328 |
| Value of total assets at beginning of year | 2011-12-31 | $1,844,076,092 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2011-12-31 | $6,920,035 |
| Total interest from all sources | 2011-12-31 | $30,519,074 |
| Total dividends received (eg from common stock, registered investment company shares) | 2011-12-31 | $11,578,624 |
| Total dividends received from registered investment company shares (eg mutual funds) | 2011-12-31 | $6,817,514 |
| Administrative expenses professional fees incurred | 2011-12-31 | $1,971,789 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2011-12-31 | $2,269,649 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2011-12-31 | $4,091,114 |
| Were there any nonexempt tranactions with any party-in-interest | 2011-12-31 | No |
| Assets. Loans (other than to participants) at end of year | 2011-12-31 | $6,640,910 |
| Assets. Loans (other than to participants) at beginning of year | 2011-12-31 | $24,026,284 |
| Other income not declared elsewhere | 2011-12-31 | $12,826,912 |
| Administrative expenses (other) incurred | 2011-12-31 | $36,924 |
| Total non interest bearing cash at end of year | 2011-12-31 | $1,614,946 |
| Total non interest bearing cash at beginning of year | 2011-12-31 | $7,488,895 |
| Value of net income/loss | 2011-12-31 | $860,203 |
| Value of net assets at end of year (total assets less liabilities) | 2011-12-31 | $1,659,091,328 |
| Value of net assets at beginning of year (total assets less liabilities) | 2011-12-31 | $1,844,076,092 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2011-12-31 | No |
| Were any leases to which the plan was party in default or uncollectible | 2011-12-31 | No |
| Assets. partnership/joint venture interests at end of year | 2011-12-31 | $124,538,963 |
| Assets. partnership/joint venture interests at beginning of year | 2011-12-31 | $90,790,595 |
| Investment advisory and management fees | 2011-12-31 | $4,824,431 |
| Value of interest in registered invesment companies (eg mutual funds) at end of year | 2011-12-31 | $10,810,495 |
| Value of interest in registered invesment companies (eg mutual funds) at beginning of year | 2011-12-31 | $15,323,052 |
| Income. Interest from loans (other than to participants) | 2011-12-31 | $788,607 |
| Interest earned on other investments | 2011-12-31 | $9,267,464 |
| Income. Interest from US Government securities | 2011-12-31 | $5,546,636 |
| Income. Interest from corporate debt instruments | 2011-12-31 | $14,852,992 |
| Value of interest in common/collective trusts at end of year | 2011-12-31 | $697,430,304 |
| Value of interest in common/collective trusts at beginning of year | 2011-12-31 | $693,243,703 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2011-12-31 | $51,910,484 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2011-12-31 | $68,120,046 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2011-12-31 | $68,120,046 |
| Interest earned from interest bearing cash (including money market accounts and certificates of deposit) | 2011-12-31 | $63,375 |
| Asset value of US Government securities at end of year | 2011-12-31 | $207,388,365 |
| Asset value of US Government securities at beginning of year | 2011-12-31 | $181,853,241 |
| Net investment gain/loss from registered investment companies (e.g. mutual funds) | 2011-12-31 | $-2,313,647 |
| Net investment gain or loss from common/collective trusts | 2011-12-31 | $-56,541,273 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2011-12-31 | No |
| Income. Dividends from preferred stock | 2011-12-31 | $336,232 |
| Income. Dividends from common stock | 2011-12-31 | $4,424,878 |
| Asset. Corporate debt instrument debt (other) at end of year | 2011-12-31 | $270,499,499 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2011-12-31 | $325,584,740 |
| Contract administrator fees | 2011-12-31 | $86,891 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2011-12-31 | $285,987,713 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2011-12-31 | $433,554,422 |
| Did the plan have assets held for investment | 2011-12-31 | Yes |
| 2010 : RIO TINTO AMERICA MASTER RETIREMENT TRUST 2010 401k financial data |
|---|
| Unrealized appreciation/depreciation of other (non real estate) assets | 2010-12-31 | $85,966,051 |
| Total unrealized appreciation/depreciation of assets | 2010-12-31 | $85,966,051 |
| Total transfer of assets to this plan | 2010-12-31 | $798,536,009 |
| Total liabilities at beginning of year (benefit claims payable, operating payabales, acquisition indebtedness and other liabilities) | 2010-12-31 | $69,167,396 |
| Total income from all sources (including contributions) | 2010-12-31 | $475,315,682 |
| Total of all expenses incurred | 2010-12-31 | $106,999,432 |
| Benefit payments and payments to participlants,beneficiaries,insurance carriers and others | 2010-12-31 | $102,114,164 |
| Total contributions o plan (from employers,participants, others, non cash contrinutions) | 2010-12-31 | $244,693,960 |
| Value of total assets at end of year | 2010-12-31 | $1,836,587,197 |
| Value of total assets at beginning of year | 2010-12-31 | $738,902,334 |
| Total of administrative expenses incurred including professional, contract, advisory and management fees | 2010-12-31 | $4,885,268 |
| Total interest from all sources | 2010-12-31 | $15,763,307 |
| Total dividends received (eg from common stock, registered investment company shares) | 2010-12-31 | $6,184,620 |
| Assets. Corporate prefeered stocks other than exployer securities at end of year | 2010-12-31 | $4,091,114 |
| Assets. Corporate prefeered stocks other than exployer securities at beginning of year | 2010-12-31 | $0 |
| Were there any nonexempt tranactions with any party-in-interest | 2010-12-31 | No |
| Assets. Loans (other than to participants) at end of year | 2010-12-31 | $24,026,284 |
| Assets. Loans (other than to participants) at beginning of year | 2010-12-31 | $0 |
| Other liabilities (not benefit claims, operating payabales oe acquisition indebtedness) at beginning of year | 2010-12-31 | $69,167,396 |
| Value of net income/loss | 2010-12-31 | $368,316,250 |
| Value of net assets at end of year (total assets less liabilities) | 2010-12-31 | $1,836,587,197 |
| Value of net assets at beginning of year (total assets less liabilities) | 2010-12-31 | $669,734,938 |
| Were any loans by the plan or fixed income obligations due to the plan in default | 2010-12-31 | No |
| Were any leases to which the plan was party in default or uncollectible | 2010-12-31 | No |
| Assets. partnership/joint venture interests at end of year | 2010-12-31 | $90,790,595 |
| Assets. partnership/joint venture interests at beginning of year | 2010-12-31 | $0 |
| Investment advisory and management fees | 2010-12-31 | $4,885,268 |
| Value of interest in registered invesment companies (eg mutual funds) at end of year | 2010-12-31 | $15,323,052 |
| Value of interest in registered invesment companies (eg mutual funds) at beginning of year | 2010-12-31 | $0 |
| Income. Interest from corporate debt instruments | 2010-12-31 | $15,763,307 |
| Value of interest in common/collective trusts at end of year | 2010-12-31 | $693,243,703 |
| Value of interest in common/collective trusts at beginning of year | 2010-12-31 | $661,672,334 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at end of year | 2010-12-31 | $68,120,046 |
| Interest-bearing cash (include money market accounts & certificates of deposit) at beginning of the Year | 2010-12-31 | $0 |
| Value of interest bearing cash (including money market accounts and certificates of deposits) at beginning of year | 2010-12-31 | $0 |
| Asset value of US Government securities at end of year | 2010-12-31 | $181,853,241 |
| Asset value of US Government securities at beginning of year | 2010-12-31 | $0 |
| Net investment gain/loss from registered investment companies (e.g. mutual funds) | 2010-12-31 | $5,155,846 |
| Net investment gain or loss from common/collective trusts | 2010-12-31 | $117,551,898 |
| Were any plan transactions or series of transactions in excess of 5% of the current value of the plan assets | 2010-12-31 | No |
| Contributions received in cash from employer | 2010-12-31 | $244,693,960 |
| Employer contributions (assets) at end of year | 2010-12-31 | $0 |
| Employer contributions (assets) at beginning of year | 2010-12-31 | $77,230,000 |
| Income. Dividends from common stock | 2010-12-31 | $6,184,620 |
| Benefit payments and payments to provide benefits directly to participlants or beneficiaries including direct rollovers | 2010-12-31 | $102,114,164 |
| Asset. Corporate debt instrument debt (other) at end of year | 2010-12-31 | $325,584,740 |
| Asset. Corporate debt instrument debt (other) at beginning of year | 2010-12-31 | $0 |
| Assets. Corporate common stocks other than exployer securities at end of year | 2010-12-31 | $433,554,422 |
| Assets. Corporate common stocks other than exployer securities at beginning of year | 2010-12-31 | $0 |
| Did the plan have assets held for investment | 2010-12-31 | No |
