Key takeaways
- Karat expresses gold purity on a 24-part scale; fineness expresses it in parts per thousand.
- 999.9 means 99.99% fine gold; 995 means 99.5% fine gold.
- In wholesale bullion markets, 995 is an important minimum purity benchmark for London Good Delivery gold bars.
- A purity mark is only one part of verification; refiner identity, serial number, assay and documentation also matter.
Karat vs fineness
Karat and fineness describe the same basic idea—how much of an item is pure gold—but they use different scales. Karat uses 24 parts, while fineness normally uses parts per thousand.
For example, 22-karat gold is approximately 916 parts pure gold per thousand, while 18-karat gold is 750 parts per thousand.
Common gold markings
- 999.9 — 99.99% fine gold, common for investment kilobars and minted bars.
- 999 — 99.9% fine gold, broadly described as 24K in consumer contexts.
- 995 — 99.5% fine gold; the minimum fineness for an LBMA Good Delivery gold bar.
- 916 — approximately 22K gold.
- 875 — approximately 21K gold.
- 750 — 18K gold.
Why bullion buyers focus on fineness
Bullion value is closely linked to fine metal content. A 1 kg bar marked 999.9 contains more fine gold than a 1 kg bar marked 995, so the purity must be considered alongside gross weight.
In professional trading, the refiner, serial number, assay information, market acceptability and condition of the bar can also affect liquidity and pricing.
Oman context
Oman’s Ministry of Commerce, Industry and Investment Promotion has published approved jewellery fineness levels including 916 for 22K, 875 for 21K and 750 for 18K gold. The Ministry also highlights national hallmark verification as part of consumer protection.