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 English-speaking world as 9-carat gold and used mainly in the jewellery sector.

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 the jewellery sector.

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

800 silver is a silver alloy with a fineness of 800 parts per thousand (80%), particularly common in German and European table silver and cutlery.

835 silver is a silver alloy with a fineness of 835 parts per thousand (83.5%), particularly typical of German and Central 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 circulation coins.

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

An alloying metal is a base or precious metal blended into a precious metal in a measured amount to deliberately shape its hardness, colour, melting behaviour or other characteristics.

An alloy is a mixture of a base metal and one or more additive metals (alloying metals) that has deliberately altered physical or chemical properties.

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

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

Fine gold refers to gold with a fineness of at least 999 parts per thousand (999), i.e. a purity of 99.9 percent or higher.

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

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

Gold plating refers to the application of a thin layer of gold onto a substrate of base or precious metal, glass or ceramic in order to improve appearance, corrosion protection 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 silver-coloured 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 is used as the primary bleaching metal to give yellow gold a silvery-white colour.

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

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

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 characteristic pink to reddish colour tone, created by a deliberate copper content.

Sterling silver is a silver alloy with 92.5% fine silver (925/1000) – the standard for cutlery, jewellery and many collector's items.

Tombac is a copper-zinc alloy with a copper content of 67-90%, known as a decorative material and historical coin metal due to its gold-like colour.

Vermeil refers to gold-plated sterling silver with a minimum gold coating of 2.5 micrometres, positioned as a distinct jewellery category between solid gold and simple gold plating.

White gold is a gold alloy blended with white metals such as palladium, nickel or silver to give it its distinctive silvery-white tone.

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