August 04, 2022 1 min read
Market Analysis: Copper spots on classic U.S. gold coins
By Steve Roach , Coin World, Published: Aug 2, 2022, 11 AM
Classic era U.S. gold coins are struck on planchets that contain 90% gold and 10% copper.
An improper mix of this alloy results in occasional copper spots seen on struck coins. These spots provide character to a coin and are a product of the minting process, though some collectors prefer coins without spots.
A 1926 American Independence Sesquicentennial commemorative $2.50 quarter eagle graded Mint State 64 by Professional Coin Grading Service has a few spots on the obverse and reverse and realized $708, with bidders responding to the nice luster in Scotsman Coin and Jewelry’s July 22 auction.
Scotsman also offered an 1891-CC Coronet gold $10 eagle graded MS-61 by PCGS that brought $3,068. The cataloger wrote on the better-date Carson City Mint issue, “Carefully detailed and somewhat lustrous, the surface shows evidence of some kind of curious greyish haziness,” adding, “Quite a number of copper spots show throughout, most of them relatively tiny.”
The original article can be found at https://www.coinworld.com/news/us-coins/market-analysis-copper-spots-on-classic-u-s-gold-coins