Units & Weight

The avoirdupois ounce (av. oz) is the mass unit used in everyday Anglo-American commerce, equal to exactly 28.349523125 grams — noticeably different from the troy ounce of 31.1035 grams used in the precious-metals trade.

The metric carat (ct) is the legal unit of weight for diamonds and other gemstones and equals exactly 0.2 grams.

Fine weight states the actual amount of pure precious metal in a bar, coin or piece of jewellery — independent of the total weight of the object.

The grain (abbreviated gr) is the smallest unit in the troy weight system and equals exactly 0.06479891 grams.

The gram (symbol g) is the base unit of mass most people work with under the International System of Units (SI) and the most widely used weight unit in the precious-metals trade.

Gross weight is the total weight of a precious-metal object including all alloying components, before any deduction for impurities or additives.

Karat (abbreviated kt or ct) is the traditional unit for the gold content of an alloy: 24 karat corresponds to pure gold (999 per mille fineness, with the highest trade purity being 999.9 per mille).

A kilo bar is a standardised precious-metal bar weighing exactly 1,000 grams (1 kg), produced for gold, silver and other precious metals in either cast or minted form.

A Japanese unit of weight from the traditional shakkan system, used today mainly in the pearl trade and equal to exactly 3.75 grams.

The troy ounce is the international standard unit for precious metal prices and equals exactly 31.1034768 grams.

The pennyweight (dwt) is a unit of mass in the troy system equal to 1/20 of a troy ounce, used above all in the Anglo-American jewellery and goldsmithing trades.

Per mille (parts per thousand) expresses the fineness of a precious metal as the proportion of pure metal in the total mass and is the legally binding figure stamped on bars and coins.

The tael is a traditional East Asian weight unit for precious metals whose exact weight varies by region between roughly 37.4 g and 37.8 g.

A long-standing South Asian measure of weight for gold and silver, the tola comes to precisely 11.6638 grams and remains in daily use across India, Pakistan and the Gulf.

The standard weight unit used worldwide in precious metal trading: one troy ounce equals exactly 31.1034768 grams of pure metal.

The troy weight system is the internationally binding scale for precious metals; its base unit, the troy ounce, equals exactly 31.1034768 grams.