The “spot price” of Precious Metals is based on an average of all the buy and sell offers in the market for that specific metal. The “spot price” Base Metal is the LME Cash Settlement Price, which is the last cash offer price for the relevant Base Metal during the day’s trading.
The spot price is published by the LBMA (for gold and silver) or the London Metal Exchange (LME) (for platinum, palladium, copper and nickel) on their websites.