What Does 850 (Platinum) Mean on Jewelry?

An 850 stamp on a platinum piece means 85% pure platinum — the lowest of the common platinum standards (850, 900, 950). It's still solid, heavy platinum with real value, just with a bit more alloy for hardness.

What is a 850 (Platinum) piece worth?

850 platinum is the lowest common platinum purity but still dense and valuable.

How to verify a 850 (Platinum) stamp

Scan the 850 PLAT mark with the Hallmark Reader to confirm it's platinum, not white gold. Anyone can stamp a mark on metal, so a hallmark alone isn't proof — the fastest way to check is to photograph the stamp and run it through the free Hallmark Reader, then confirm the metal itself with the Is It Real? tool. For a full picture of what your piece is worth, get a free jewelry appraisal. To compare 850 (Platinum) with every other mark side by side, see the full jewelry stamps and markings chart.

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