Company: RTNTF
Filing Date: 2025-02-20
Form Type: 20-F
Source: 0001628280-25-006642
Chunk: 352

Company: RIO TINTO LTD
Filing Date: 2025-02-20
Form: 20-F
Chunk 352
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 jointly with our own production. Average costs are calculated by reference to the cost levels experienced in the relevant month together with those in opening inventory. The cost of raw materials and purchased components, and consumable stores, is the purchase price. The cost of work in progress and finished goods and goods for resale is generally the cost of production, including directly attributable labour costs, materials and contractor expenses, the depreciation of assets used in production and production overheads. Work in progress includes ore stockpiles and other partly processed material. Stockpiles represent ore that has been extracted and is available for further processing. If there is significant uncertainty as to if and when the stockpiled ore will be processed, the cost of such ore is expensed as mined. If the ore will not be processed within 12 months after the balance sheet date, it is included within non-current assets and net realisable value is calculated on a discounted cash flow basis. Quantities of stockpiled ore are assessed primarily through surveys and assays. Certain estimates, including expected metal recoveries, are calculated using available industry, engineering and scientific data, and are periodically reassessed, taking into account technical analysis and historical performance.

|                                              | 2024US$m | 2023US$m |
| Raw materials and purchased components       |      971 |    1,050 |
| Consumable stores                            |    1,560 |    1,520 |
| Work in progress                             |    1,931 |    2,467 |
| Finished goods and goods for resale          |    1,620 |    1,836 |
| Total inventories                            |    6,082 |    6,873 |
| Comprising:                                  |          |          |
| Expected to be used within one year          |    5,860 |    6,659 |
| Expected to be used after more than one year |      222 |      214 |
| Total inventories                            |    6,082 |    6,873 |

During 2024 , the Group recognised a net inventory write-off of US$ 49million ( 2023 : US$ 60million write-off). This included inventory write-offs of US$ 77million ( 2023 : US$ 94million ) partly offset by a write-back of previously written down inventory due to an increase in realisable values amounting to US$ 28million ( 2023 : US$ 34million ). At 31 December