Gold imitations

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An imitation gold is a metal or alloy that looks like gold . Mainly because of the high price of gold, alloys made of base metals have been developed that are used as gold imitation or as a base in the manufacture of doublé . In most cases, these are non-standardized copper alloys with a wide variety of additives.

If such an alloy consists of at least 50% copper, sometimes even slightly below, combined with zinc as the main alloy (up to more than 44%), it is called brass . Sometimes up to 3% lead is contained here in order to increase the machinability of the brass , which is not easy to process. If the copper content of the brass rises to over 67%, it is called tombac . Of special brass occurs when small amounts of aluminum , iron , manganese , nickel , silicon , tin or, in rare cases, of gold are alloyed. Precious metals are also used to make alloys that can appear like gold without any gold in them. With some alloys, however, gold itself is also added in small amounts.

Customary terms

Names of gold imitations and gold-like alloys and their respective composition:

  • Abyssinian gold is the name for a brass alloy made of approximately 90–92% copper, 8–10% zinc, plated with up to 1% gold
  • Gold leaf, fake - A tombac alloy with a gold-like hue and high ductility. The composition consists of approx. 75–85% copper, alloyed with zinc.
  • Chrysorin - similar to the previous one, with 30% zinc and 70% copper.
  • Cooper's Gold - A golden yellow platinum alloy, consisting of 80% platinum and 20% copper.
  • Cupror - This alloy is named after the Latin word for copper, cuprum , and the French word for gold, or . It is an aluminum bronze made of copper with an addition of 5 to 5.8% aluminum. The color of the alloy is very similar to that of gold.
  • Dixigold - This is an aluminum bronze made from 10% aluminum and 90% copper. It is very hard and acid-proof.
  • French gold - This is Rottombak made from 10 to 31.52% zinc, sometimes 0.48% tin, the rest is copper. The name Oreïde is also used for it, derived from the French word for gold, or . This alloy is used for belt goods or, more rarely, for cutlery.
  • Gold bronze - This is used to refer to two different alloys. 1. A gunmetal alloy of golden yellow color, which consists of 90.5% copper with an addition of 6.5% tin and 3% zinc. 2. An aluminum bronze containing real gold, consisting of 3–8% aluminum, 2% gold and 90–95% copper.
  • Gold anodized - gold-colored, electrically oxidized aluminum e.g. B. for costume jewelry, see anodizing .
  • Gold Imitation - This is a gold-colored aluminum bronze made from 2% aluminum, 0.2% real gold and 97.8% copper. Paul Lazard and Louis Emmanuel Daniel from Paris received a German patent number 47380 for this alloy in 1889.
  • Gold Copper - A gunmetal alloy made from 3% zinc, 6.5% tin, and 90.5% copper.
  • Gold foam metal - This tombac alloy has a particularly high ductility and is therefore used to produce fake gold leaf. It consists of 15.5–22.2% zinc; the rest is copper.
  • Gold Tombac - This tombac contains 15% zinc. The rest is again copper. This alloy is also called middle tombac .
  • Heyden gold - foil made of non-oxidizing bronze instead of gold leaf.
  • Mannheimer Gold - A gunmetal made of 9.3% zinc, 7% tin and an amount of copper corresponding to the rest is named here. A protected trade name for the same alloy composition is Similor .
  • Mosaic gold - For once , this is not a special alloy. Mosaic gold is a protected trade name for semi-finished products made of different colored (real) gold alloys for the manufacture of jewelry. Semi-finished products are partially preprocessed materials; in this case it is sheets and strips. However, this term is sometimes incorrectly used as a substitute name for the similar-sounding protected product name Mosaic Gold (see following point), which is why it is listed here.
  • Mosaic gold - This is a protected trade name for golden yellow brass and tombac alloys made from 25–37% zinc and the corresponding residual amount of copper.
  • Shell gold - a brass alloy consisting of 53.5% zinc and 46.5% copper. It's very brittle. It is used to make buttons.
  • Nordic Gold - A non-magnetic alloy of good gold color made from 89% copper, 5% aluminum, 5% zinc and 1% tin. This alloy is used to manufacture euro coins with the denominations of 50, 20 and 10 euro cents and was previously used as a coin alloy in some countries.
  • Nuremberg Gold - As with the gold imitation and gold bronze, real gold is also contained here. It is an aluminum alloy of approx. 7–8% aluminum, 2–3% gold and 90% copper.
  • Oreïde - The alloy, also known as French gold , got its name from a derivation of the French word for gold, or . It is a gold-colored tombac alloy made from 10–15% zinc. The rest is made of copper. This alloy is used for belt goods or, more rarely, for cutlery.
  • Paris Talmigold - This special brass also contains real gold. The alloy consists of copper with an addition of 8.9% zinc and 0.9% gold. It has a golden yellow color and good elasticity. That is why it is used for jewelry and body goods, which are then gilded. It was named after the Parisian manufacturer Tallois , who in 1840 brought a copper alloy consisting of 87% copper, 12% zinc and 1% tin onto the market, which was plated with a gold layer that was rolled on or galvanically applied. It was traded as Tal lois-de mi -or , composed of its name and the French term de mi-or for half gold. This became the later Talmigold and its modified name.
  • Princess metal - Another spelling for this is princess metal . It is a golden yellow brass alloy made of 66.7% copper and 33.3% zinc.
  • Rauschgold - The term rushing brass is also used for this. These are thin brass foils with a thickness of 10 to 30 nm. These foils "rustle" when you touch them.
  • Similor - This is a protected trade name that derives its name from the combination of the Latin word similis for similar and the French word for gold, or . It is a gunmetal made of 9.3% zinc, 7% tin and a corresponding amount of copper. This alloy is also known as Mannheim gold.
  • Talmigold - See Paris Talmigold .
  • Yellow Metal - This is a brass alloy made of 60% copper and 40% zinc used for ironwork.

Individual evidence

  1. ↑ a b Jochem Wolters: The gold and silversmith. Volume 1 - Materials and Materials. 2nd, revised edition 1984. Stuttgart, Rühle-Diebener-Verlag. Chapter 1.4.8 Copper and its alloys .
  2. ↑ a b c d e Georg Buchner: Auxiliary book for metal technicians: Introduction to modern metal and alloy science, tried and tested working methods and regulations for metal technicians' workshops, surface finishing work, among other things, along with scientific explanations. 3rd edition, Springer-Verlag, 2013. ISBN 9783642914409 . Pp. 36, 38, 39, 40.