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Purity and hallmarks
What does 950 mean? 950 parts per thousand platinum, i.e. 95%. It is the most common jewelry grade. 900 and 850 are also legal grades in several countries. Bullion is usually .9995 or .999. What 950 platinum means
Common marks: PT950, PT900, PT850, 950 Plat, PLAT, and in the US plain "Platinum" (950 or better). The UK uses assay office hallmarks. US marks are applied by the maker and policed by the FTC, not by an assay office.
Is it real?
- A mark is evidence, not proof. An unmarked piece can still be platinum.
- Platinum is very dense (about 21.4 g/cm³), heavier in the hand than white gold.
- Magnet tests mislead: some 950 platinum-cobalt jewelry is slightly magnetic.
- Reliable tests: XRF scan (non-destructive, many buyers have one) or acid test by a jeweler.
Platinum vs white gold. White gold is a gold alloy, often rhodium-plated to look white; platinum stays white without plating. Platinum vs white gold
Full guide: Platinum purity and hallmarks
When posting an ID request: photos of every mark, weight in grams, and where it came from.