Gold Purity Explained: 585, 750 or 999.9 — and How to Work Out the Price per Gram

585, 750 or 999.9 — the number stamped on gold tells you how much pure metal it holds. Here is a purity chart, a formula for the price per gram, and why investors buy 999.9.

Gold purity (fineness) tells you how many parts of pure gold there are in 1,000 parts of the metal. One gram of 585 gold holds 0.585 g of pure gold, 750 gold holds 0.75 g, and 999.9 gold is virtually pure. That is why a gram of 585 gold is worth about 41% less in metal than a gram of 999.9.

01Fineness vs karats

Fineness measures purity in parts per thousand; karats measure it in 24 parts. 24 karat is pure gold. 18 karat = 18 ÷ 24 = 750 fineness, and 14 karat = 583 or 585.

The rest of the alloy is other metals — copper, silver, palladium. They give jewellery its strength and colour.

02Gold purity chart

*The example assumes 340 GEL per gram of 999.9 gold. The live price updates every 10 seconds on the Gold.ge gold price page.

03How to calculate the price of 1 gram

If a gram of 999.9 gold costs 340 GEL, the metal in a gram of 585 gold is worth about 198.9 GEL. A 10 g ring in 585 gold contains 5.85 g of pure gold — about 1,989 GEL of metal.

Keep in mind: this is metal value only. Jewellery sells for more in a shop because the price includes craftsmanship and design. When you sell it, you are usually paid for the metal alone — and often less.

04Why investors choose 999.9

• You pay for metal, not design. 999.9 means 99.99% pure gold.
• The price tracks the market. An investment bar is priced off the global spot price. The bigger the bar, the lower the premium, so larger bars are better value for investing.
• Recognised refiners. Valcambi, PAMP, Argor-Heraeus and C. Hafner bars are recognised in any country.
• Everything is stamped on the bar. Weight, fineness, refiner and serial number; small bars come sealed in a certificate card.

→ Gold bars · 100 g Valcambi bar

05Coins: does 916.7 mean less gold?

No. The Krugerrand is 916.7 fine (22 karat), but the coin weighs about 33.93 g and contains exactly one troy ounce — 31.10 g of pure gold. The Maple Leaf is 999.9 fine and contains the same 31.10 g. Both hold the same amount of gold; the copper in the Krugerrand simply makes it more scratch-resistant.

Historic coins are often 900 fine. The Nicholas II 10 roubles, for example, weighs 8.6 g and contains 7.74 g of pure gold. Coins like this also carry historic value, so their price is not set by metal alone.

Rule of thumb: when comparing coins, look at the pure gold weight, not just the fineness.

→ Krugerrand · Maple Leaf · Nicholas II 10 roubles · All gold coins

06How to check purity when you buy

1. The hallmark. Jewellery shows the fineness as a number (585, 750). A bar should show its weight, fineness (999.9), refiner and serial number.
2. The paperwork. Ask for a receipt or certificate that states fineness and weight.
3. The seller. Gold bought privately is hard to verify — buy from a shop that names the refiner and origin of the bar.
4. The price. If 999.9 gold is offered well below the market price, be suspicious.

07FAQ