Thread: USA Army ring
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Old 08-14-2019, 09:37 AM   #6
Johnny Peppers
Johnny Peppers is offline
Join Date: Feb 2010
Location: Arkansas
Posts: 2,860

Curious as to how you tested the purity out to three decimal places. The standard is to use a touchstone, a very fine abrasive stone, and acid of a known strength. Nitric acid for 10K and 14K, and a mix of nitric and hydrocloric acid for higher karat.

American jewelers are alllowed a percentage of leeway in the actual gold content.

Even European jewelery that is marked by percentage is not exact unless so marked. 417 = 10K, 585 = 14K, and 750 = 18K, but the percentage mark is followed by a letter ( a P maybe) if the mark is exact.
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