Troy Ounce (ozt)

When you see a gold or silver price on any market data screen, the number shown is always the price per troy ounce — abbreviated ozt or sometimes simply oz t. This is not the same ounce used to measure, say, a bag of flour. The troy ounce traces back to medieval European trade and was standardized for precious metals because consistency in small, high-value weights was commercially critical.

The difference sounds small — roughly 2.75 grams — but it compounds fast. Suppose a bar of gold contains 400 troy ounces (a standard wholesale "Good Delivery" bar). Calculating its value using regular avoirdupois ounces instead would understate the weight by about 10%, a meaningful error at any price level. This is why the commodity units and contracts guide treats units as a core concept rather than a footnote.

All four major precious metals — gold, silver, platinum, and palladium — are quoted per troy ounce on global exchanges. Futures contracts on those metals also define their size in troy ounces; a standard COMEX gold contract, for example, covers 100 troy ounces. Prices shown on the commodities page follow this same convention. For a deeper look at how gold specifically is quoted and traded, see the gold explained guide.

The single most common reader confusion: seeing a gold price and assuming it refers to a regular ounce. It never does. Any professional precious-metals quote — spot, futures, or wholesale — is always troy.