Nickel silver

"German silver" hair comb by Bruce Caesar (Pawnee), Oklahoma, 1984

Nickel silver, also known as German silver,^[1] Argentann,^[1] new silver,^[1] nickel brass,^[2] albata,^[3], or alpacca,^[4] is a copper alloy with nickel and often zinc. The usual formulation is 60% copper, 20% nickel and 20% zinc.^[5] Nickel silver is named for its silvery appearance, but it contains no elemental silver unless plated. The name "German silver" refers to its development by 19th-century German metalworkers in imitation of the Chinese alloy known as paktong^[6][7] All modern, commercially important nickel silvers (such as those standardized under ASTM B122) contain significant amounts of zinc, and are sometimes considered a subset of brass.^[8]

Uses

Nickel silver first became popular as a base metal for silver-plated cutlery and other silverware, notably the electroplated wares called EPNS (electro-plated nickel silver). It is used in zippers, better-quality keys, costume jewellery, for making musical instruments (e.g., cymbals, saxophones), and is preferred for the track in electrically powered model railway layouts, as its oxide is conductive. It is widely used in the production of coins (e.g. Portuguese escudo and the former GDR marks, ). Its industrial and technical uses include marine fittings and plumbing fixtures for its corrosion resistance, and heating coils for its high electrical resistance.

In the 19th century, particularly after 1868, Plains Indian jewelers were able to easily acquire sheets of German silver. They used them to cut, stamp, and cold hammer a wide range of accessories and horse gear. Continuing into the present, Plains metalsmiths have used German silver for pendants, pectorals, bracelets, armbands, hair plates, conchas, earrings, belt buckles, necktie slides, stickpins, dush-tuhs, and tiaras.^[9] Nickel silver is the metal of choice among contemporary Kiowa and Pawnee metalsmiths in Oklahoma.

Early in the twentieth century, German silver was used by automobile manufacturers before the advent of steel sheet metal, i.e., the famous Rolls Royce Silver Ghost of 1907. After about 1920, its use became widespread for pocketknife bolsters, due to its machinability and corrosion resistance. Prior to this point, the most common metal was iron.

Musical instruments, including the flute, saxophone, trumpet, and French horn, can be made of nickel silver. For example, some leading saxophone manufacturers, such as Keilwerth,^[10][11] Selmer, P.Mauriat, Yanagisawa, and Yamaha, offer saxophones made of nickel silver, though these are far rarer than traditional brass bodied saxophones. It is said to produce a bright and powerful sound quality; an additional benefit is that nickel silver does not require a lacquer finish. It is the most commonly used material for woodwind keys. Most clarinets, oboes and similar wind instruments have nickel silver keys, normally silver plated. It is used to produce the tubes (called staples) onto which oboe reeds are tied. It was used in the construction of the National tricone resophonic guitar. The frets of guitar, mandolin, banjo, bass, and related string instruments are typically made of nickel silver.

Toxicity

According to the Merck Manual, prolonged contact of copper alloys with acidic food or beverages (including boiling milk) can leach out the copper and cause toxicity.^[12] Long term, low doses can lead to cirrhosis.

History

Nickel silver was first known and used in China. It became known in the west from imported wares called bai-tong or pakfong (白銅, literally "white copper"), for which the silvery metal colour was used to imitate sterling silver. According to Berthold Laufer, it was identical with khar sini, one of the seven metals recognized by Jābir ibn Hayyān.^[13]

In the 18th century, researchers found it was a copper-nickel-zinc alloy . In 1770 the Suhl (Germany) metalworks were able to produce a similar alloy.^[14] In 1823 a German competition was held to perfect the production process: the goal was to develop an alloy that possessed the closest visual similarity to silver. The brothers Henniger in Berlin and Ernst August Geitner in Schneeberg independently achieved this goal. The manufacturer Berndorf named the trademark brand Alpacca, which became widely known in northern Europe for nickel silver. About the same time in 1832, a form of German silver was also developed in Birmingham, England.^[15]

After 1840, the development of electroplating caused nickel silver to become widely used. It formed an ideal, strong and bright substrate for the plating process. It was also used unplated in applications such as cheaper grades of cutlery.

Fraudulent uses

Counterfeit Morgan Dollar (right) compared to a genuine American Silver Eagle (left)

Counterfeiters have used nickel silver to produce coins and medallions purporting to be silver rounds, generally in an attempt to trick unsuspecting buyers into paying prices based on the spot price of silver. The metal has also been used to produce counterfeit Morgan dollars.

Nickel silver fraud has included the production of replica bullion bars, marked "Nickel Silver" or "German Silver", in weights of one troy ounce. They are sold without notification that they contain no elemental silver.

See also

• Cupronickel
• Britannia metal (approx' 93% tin, 5% antimony, and 2% copper)
• Sheffield plate

References

1. ^ ^{a b c} Principles of Metallurgy. p. 62. ISBN 9781440056994. http://books.google.de/books?id=GSR1U4R0e84C&pg=PA62. 
2. ^ Gayle, Margot; Look, David W; Waite, John G (1993-04). Metals in America's Historic Buildings: Uses and Preservation Treatments, Pt. 1, A Historical Survey of Metals, Pt. 2, Deterioration and Methods of Preserving Metals. p. 35. ISBN 9780160616556. http://books.google.de/books?id=CtD5ucVtLMcC&pg=PA35. 
3. ^ Oxford English Dictionary
4. ^ http://www.ascasonline.org/articoloDICEM104.html
5. ^ Tim McCreight, The Complete Metalsmith.
6. ^ Samuel J. Rosenberg. Nickel and its alloys. Monograph ; 106. National Bureau of Standards. p. 8.6. 
7. ^ Keith Pinn, Paktong: The Chinese Alloy in Europe
8. ^ Nickel Silver - retrieved 19 April 2010.
9. ^ Dubin, Lois Sherr. North American Indian Jewelry and Adornment: From Prehistory to the Present. New York: Harry N. Abrams, 1999. ISBN 0-8109-3689-5., p. 290-293.
10. ^ http://www.schreiber-keilwerth.com/englisch/keilwerth/instruments/bari_sx90r_shadow.htm
11. ^ http://www.saxophones.co.uk/keilwerth_saxophones.htm
12. ^ Merck Manual of Diagnosis and Therapy, 17th ed., p. 56
13. ^ Holmyard, E. J. (1957). Alchemy, p. 80. New York: Dover.
14. ^ Neumann, Bernhard (1904). Die Metalle: Geschichte, Vorkommen und Gewinnung, nebst ausführlicher Produktions- und Preis-Statistik. Vom "Verein zur Beförderung des Gewerbefleisses" preisgekrönte Arbeit. p. 327. http://books.google.de/books?id=vBFKAAAAMAAJ. 
15. ^ Neumann, B. (1903). "Die Anfänge der Argentan- (Neusilber)-Industrie und der technischen Nickelerzeugung". Zeitschrift für Angewandte Chemie 16: 225. doi:10.1002/ange.19030161004.