This is the second part of an entry submitted by Dick Johnson from his Encyclopedia of Coin and Medal Terminology. Thanks. -Editor
Goldplate, Goldplating
How to tell goldplate from solid gold. Goldplate cannot be distinguished from solid gold by surface inspection. A test of nitric acid or touchstone
will not differentiate the two. A tiny test cut is usually done on the edge of medals, searching for the color of gold or the base metal. This is not foolproof either as medal
makers often choose a base metal of yellow brass or oroide because it will bleed yellow as does gold. (A nitric acid test at a test cut would reveal the base metal is not gold.
See gold.)
The most obvious difference will be the object's weight. Solid gold will be heavier. Thus a specific gravity test will not only reveal the solid gold status (versus
goldplate) but also will reveal the karat content (from 24 karat down to 9 karat; 8 karat and less is too similar to the specific gravity of other metals). Pure 24 karat and 22
karat is more than twice as heavy as most plated compositions. Such a nondestructive specific gravity test is obviously recommended over the destructive form of a test cut.
Marking goldplated objects. Goldplated objects are not required to be marked in any way unless the base metal is another precious metal. Solid gold objects are,
of course, required to be marked with their true fineness in most industrial countries (since 1904 in England, 1906 in America). This is a current obligation reflecting the
heritage of hallmarking in which all gold and silver objects were marked with symbols to identify the true nature and fineness of the metal. (The U.S. Mint does not honor this
law, however, and their 20th century gold medals are unmarked.)
Now more progressive medal makers are revealing the nature of the base metal and better goldplated medals are edgelettered with the identity of the base metal and, often, the
karat of the plated metal. This precludes the need of making a test cut, mentioned above, to see if an object is solid or plated. See edge lettering and numbering.
Reverse goldplating. Electrolysis can remove gold from a surface as well as add metal – in effect stripping off the gold from the surface of a goldplated item. By
reversing the electric current the cathodic object becomes the anode and gives up the gold on its surface. The anode becomes the cathode and the gold collects on its surface.
Previously depletion gilding obtained the same effect with firegilded objects. (Such objects need to be refinished quickly because this process creates an activated surface.)
Goldplated medals. The first goldplated medals were plated at silverware factories. Later (and particularly in 1890s) this was accomplished by jewelry
manufacturers. Only in the 20th century were goldplated medals made by traditional medal makers; the wide popularity of "gold" award medals required medal manufacturers
to provide goldplating as a necessary service to their clients.
Silver medals were goldplated to create vermeil (particularly after 1960 for the bullion medal demand). Bronze medals were goldplated and silverplated to create the
gold-silver-bronze medal rank like those used for the Olympics.
Plating by national mints. Generally, goldplating is never done by a national mint. Coins intended for circulation, or medals intended for public sale, may be
struck of a gold clad composition but never plated inside the mint. The U.S. Mint has never had the equipment nor the authority to electroplate a numismatic item of their
manufacture. In certain instances these have been done outside the mint:
• A new design in 1883 of the U.S. five-cent piece (without the word cent) was goldplated outside the mint by unscrupulous persons whose intent was to passed them off as $5
gold pieces.
• Exposition officials of the Panama-Pacific Expo in 1915 wanted a goldplated version of their medal designed by John Flanagan and struck at the Philadelphia Mint. The
goldplating was accomplished by Tiffany & Co in one of its jewelry plants.
• The issuance of a goldplated John Wayne Medal of 1979, was struck in bronze by the Philadelphia Mint, but was goldplated outside the mint by private companies.
Imitation gold. While goldplating is done to imitate solid gold (at a fraction of the cost), imitation goldplating can be accomplished with a gold tint lacquer
(at even further savings in cost). References:
F1 {1876} Zowey.
F2 {1949} Blum and Hogaboom.
F3 {1954} Graham.
F4 {1963} Brenner.
F5 {1974} Lowenheim.
F6 {1975} Lins and Oddy.
F7 {1986} Rubenstein.
F8 {1987} Romankiew.
To read the earlier E-Sylum article, see:
VOCABULARY TERMS: GOLDPLATE, GOLDPLATING, PART 1 (https://www.coinbooks.org/v22/esylum_v22n45a17.html)
This is a very informative entry. I learned a lot, and expect many readers did as well. I was unaware of the process of reverse electroplating, for instance. -Editor
Book lovers should be word lovers as well.
Looking for the meaning of a numismatic word, or the description of a term? Try the Newman Numismatic Portal's Numismatic Dictionary at: https://nnp.wustl.edu/library/dictionary
Or if you would like a printed copy of the complete Encyclopedia, it is available. There are 1,854 terms, on 678 pages, in The Encyclopedia of Coin and Medal
Technology. Even running two a week would require more than 19 years to publish them all. If you would like an advance draft of this vital reference work it may be obtained
from the author for your check of $50 sent postpaid. Dick Johnson, 139 Thompson Drive, Torrington, CT 06790.
Wayne Homren, Editor
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