Precious Metals

Most jewelry is constructed with a precious metal and alloyed with other metals to make it stronger and less expensive. Stamps and hallmarks are stamped on the piece to indicate the purity of the precious metal, and the maker.

A Hallmark is the maker’s mark. Tiffany, Cartier, or JJ for Jonathan’s Jewelers.

A purity mark is done by numbers indicating how much metal is precious vs alloy.

Gold:

    • 999 – 24k 100% pure gold
    • 916 – 22k 92% gold : 8% alloy
    • 750 – 18k 75% gold : 25% alloy
    • 585 – 14k 58% gold : 42% alloy
    • 416 – 10k 41% gold : 59% alloy
    • 375 – 9k 37% gold : 62% alloy
    • 333 – 8k 33% gold : 66% alloy

Silver – pure is very soft, so it is alloyed mostly with copper

    • 925 – sterling silver
    • 800 – coin silver

Platinum – is often alloyed with iridium, cobalt, or chromium.

    • 900 PL – IRID is the common stamp
    • 900 PT – 90% pure platinum

Palladium – is often 100% pure and marked pd.