Purity & Alloys

333 gold is a gold alloy with a fineness of 333 parts per thousand (33.3 %), equivalent to 8 carat, used mainly in the jewellery trade.

375 gold is a gold alloy with a fineness of 375 parts per thousand (37.5 %), known across the English-speaking world as 9 carat gold and used chiefly in jewellery.

585 gold is a gold alloy with a fineness of 585 parts per thousand (58.5 %), matching the international 14 carat standard and widely used in jewellery.

750 gold is a gold alloy with a fineness of 750 per mille (75.0 %), equal to 18 carat, and the most widely used quality in the jewellery and watchmaking industries.

800 silver is a silver alloy with a fineness of 800 parts per thousand (80 %), found above all in European table silver and cutlery.

835 silver is a silver alloy with a fineness of 835 per mille (83.5 %), especially typical of Central European cutlery and jewellery of the 19th and early 20th centuries.

900 gold is a gold alloy with a fineness of 900 per mille (90 %), equivalent to 21.6 carat - a historically important standard for European and American circulating coins.

916 gold is a gold alloy with a fineness of 916.6 parts per thousand (22 carat), used worldwide above all for premium jewellery and bullion coins.

An alloy is a mixture of a main metal and one or more additional metals (alloying metals) that deliberately possesses altered physical or chemical properties.

An alloying metal is a base or precious metal added to a precious metal in a defined proportion in order to deliberately change its hardness, colour, melting behaviour or other properties.

Britannia silver is a silver alloy of 958 fineness (95.8 %), introduced in England in 1697 as a higher standard alongside sterling silver (925).

Fine gold denotes gold with a fineness of at least 999 thousandths (999 ‰), meaning a purity of 99.9 per cent or higher.

Fine gold content states what proportion of a gold alloy consists of pure gold, expressed in thousandths (per mille) or in carats.

Fineness states how much pure precious metal an alloy contains — expressed in thousandths (e.g. 999) or in carats (e.g. 585 = 14 carat).

Gold double is a base-metal core (usually brass or copper) that is mechanically bonded to a thick layer of gold by hot rolling — as opposed to electroplated gold plating.

Gold plating is the deposition of a very thin layer of gold onto a base or precious metal, glass or ceramic substrate to improve appearance, corrosion resistance or electrical performance.

Green gold is a gold alloy with a high silver content, which gives the metal a characteristic greenish-yellow tint.

Nickel silver is a silvery copper-nickel-zinc alloy that contains no silver whatsoever; its appearance made it a popular silver substitute throughout history.

Nickel white gold is a gold alloy in which nickel serves as the main whitening metal, giving yellow gold a silvery-white colour.

Palladium white gold is a gold alloy in which palladium acts as the key alloying metal, giving the gold its characteristic silvery-white colour.

Red gold is a gold alloy with a high copper content that gives the metal its distinctive reddish to warm bronze-coloured tone.

An electroplated rhodium layer applied to jewellery or coins that improves lustre, scratch resistance and protection against tarnishing.

Rose gold is a gold alloy with a distinctive pink to reddish hue created by a deliberate copper content.

Sterling silver is a silver alloy containing 92.5% fine silver (925/1000) — the standard for cutlery, jewellery and many collector pieces.

Tombac is a copper-zinc alloy containing between 67% and 90% copper; its gold-like colour has long made it a favourite decorative material and a traditional coin metal.

Vermeil is gold-plated sterling silver carrying a minimum gold layer of 2.5 micrometres, forming a distinct jewellery category that sits between solid gold and ordinary gold plating.

White gold is a gold alloy to which white metals such as palladium, nickel or silver are added to produce its characteristic silvery-white colour.

Yellow gold is the classic gold alloy of gold, silver and copper, whose warm yellow tone comes closest to that of the pure metal.