| 13. | REVENUE RECOGNITION |
Revenue is recognised to the extent that it is probable that economic benefits will flow to the Group and the amount of revenue can be reliably measured. Revenue is stated at the fair value of the consideration received or receivable.
Revenue arising from gold, copper and silver sales is recognised when the significant risks and rewards of ownership pass to the buyer. The price of gold, copper and silver is determined by market forces.
Copper and gold concentrate revenue is calculated, net of refining and treatment charges, on a best estimate basis on shipment date, using forward metal prices to the estimated final pricing date, adjusted for the specific terms of the agreements. Variations between the price recorded at the shipment date and the actual final price received are caused by changes in prevailing copper and gold prices, and result in an embedded derivative in the trade receivable. The embedded derivative is marked-to-market each period until final settlement occurs, with changes in fair value classified as provisional price adjustments and included as a component of revenue.