PT950 (platinum)
The metal is platinum: at least 950 parts in every 1,000 are pure platinum.
How to read it
The FTC’s jewelry guides allow Plat. or Pt. as the abbreviation for platinum, and allow metal of at least 950 parts per thousand pure platinum to be marked platinum. Metal of 850 or 900 parts per thousand may be marked platinum only with the number before it, which is where marks like PT900 come from.
Also searched as: 950 Plat, Plat, PT900, Pt950, PT950.
A stamp is a claim about the metal, made by whoever struck it. This page says what each mark means under the rules that define it; it doesn’t test or value anything.
Platinum in UK hallmarks
The UK’s Hallmarking Act lists four platinum standards, 850, 900, 950 and 999, and gives 950 and 999 platinum an optional picture mark of its own: an orb surmounted by a cross.
More jewellery marks
Sources
- Guides for the Jewelry, Precious Metals, and Pewter Industries (16 CFR Part 23), 16 CFR Part 23 (1 January 2021 edition), Federal Trade Commission, published by the U.S. Government Publishing Office, § 23.7(c)
- Hallmarking Act 1973, Schedule 2: Approved Hallmarks, Hallmarking Act 1973 (c. 43), Sch. 2, legislation.gov.uk (The National Archives), Sch. 2, Pt. I, paras. 2 and 3
Last reviewed September 27, 2026 by Rory Hansen. How we research