Purity & Alloys

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

375 gold denotes a gold alloy with a fineness of 375 parts per thousand (37.5%), known in the UK and other English-speaking countries as 9-carat gold and used mainly in jewellery.

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

750 gold denotes a gold alloy with a fineness of 750 parts per thousand (75.0%), corresponding to 18 carats, and is the most-used quality in the jewellery and watch industry.

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

835 silver is a silver alloy with a fineness of 835 parts per thousand (83.5%), particularly typical of continental European cutlery and jewellery of the 19th and early 20th centuries.

900 gold denotes a gold alloy with a fineness of 900 parts per thousand (90%), corresponding to 21.6 carats – a historically important standard for European and American circulating coins.

916 gold denotes a gold alloy with a fineness of 916.6 parts per thousand (22 carats), used worldwide above all for high-quality jewellery and investment coins.

An alloying metal is a base or precious metal added to a precious metal in a defined quantity to deliberately alter hardness, colour, melting behaviour or other properties.

An alloy is a mixture of a main metal and one or more additive metals (alloying metals), created deliberately to give it altered physical or chemical properties.

Britannia silver refers to a silver alloy with a fineness of 958 ‰ (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 parts per thousand (999 ‰), i.e. a purity of 99.9 per cent or higher.

Fine gold content indicates the proportion of a gold alloy that consists of pure gold, expressed in parts per thousand (per mille) or carats.

Fineness indicates how much pure precious metal is contained in an alloy – expressed in parts per thousand (e.g. 999) or in carats (e.g. 585 = 14 carat).

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

Green gold is a gold alloy with a high silver content that gives the metal a characteristic greenish-yellow hue.

Nickel silver is a silvery copper-nickel-zinc alloy containing no silver at all, historically used as a silver substitute because of its appearance.

Nickel white gold is a gold alloy in which nickel serves as the primary whitening metal to give yellow gold a silvery-white colour.

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

A gold alloy carrying a substantial share of copper, red gold takes on a distinctive reddish, warm bronze-like colour thanks to that copper.

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

Rolled gold is a base-metal core (usually brass or copper) that is mechanically bonded to a thick layer of gold by hot rolling – in contrast to electrolytic gold plating.

Rose gold is a gold alloy with a characteristic pink to reddish hue that arises from 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 items.

Tombac is a copper-zinc alloy with a copper content of 67–90%, known for its gold-like colour as a decorative material and historic coinage metal.

Vermeil is gold-plated sterling silver with a minimum gold layer of 2.5 microns, positioned as a distinct jewellery category between solid gold and simple gold plating.

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

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