What does PT900 mean on jewelry?
PT900 means 85–90% platinum (Platinum). Solid precious metal
Solid platinum, still high value by weight. At today's price the metal is worth about $41.64 per gram.
What the mark tells you
Lower platinum standards, more common in Japanese and older European work.
You may also see it written as 900pt, 850, pt850. They all mean the same thing.
What PT900 is worth by weight, today
A piece stamped PT900 is 90.0% platinum, so at today's spot price the metal in it is worth $41.64 per gram. A buyer will offer 70–90% of that — they carry the refining cost and take a margin — and anything below about 60% is a poor offer.
| Weight | Metal value | Likely offer |
|---|---|---|
| 1 g | $42 | $29 – $37 |
| 3 g | $125 | $87 – $112 |
| 5 g | $208 | $146 – $187 |
| 10 g | $416 | $291 – $375 |
| 20 g | $833 | $583 – $749 |
| 50 g | $2,082 | $1,457 – $1,874 |
Weigh the piece without stones if you can. A typical ring is 3–6 g, a 45 cm chain 8–15 g, a bangle 15–30 g. Stones, solder and springs add weight that is not platinum.
Is it worth anything?
Solid platinum, still high value by weight.
Marks often confused with PT900
| Mark | Means | Worth |
|---|---|---|
| PT950 | 95% platinum | Solid metal |
Where to find it
On a ring the mark is almost always inside the band. On a chain or bracelet look at the clasp or the tag beside it; on earrings check the post or the back. Marks are tiny and often worn — a phone camera zoomed all the way in usually reads one better than your eye does.
A stamp is evidence, not proof
Marks wear down, are struck only partially, and are occasionally forged outright. If a piece is valuable enough to matter, have the metal tested rather than relying on the stamp alone. Equally, an absent stamp does not always mean an absent metal: older and handmade jewelry is frequently unmarked.
Found something real? Value it
If the piece is solid metal or holds a stone, see what it is actually worth — both at retail and what you would genuinely be offered for it.
Value my jewelry