Fine Gold Content
Also: Gold Content, Gold Fineness, Gold Titre
Fine gold content indicates what proportion of a gold alloy consists of pure gold, expressed in thousandths (per mille) or karats.
Fine gold content describes the percentage of pure gold in a gold alloy. It is the key figure when buying, selling, and valuing gold coins, gold bars, and gold jewellery – because not every piece of "gold" contains equal amounts of the valuable precious metal. The higher the fine gold content, the more valuable the piece is relative to its weight. The current gold price always refers to pure fine gold (999.9).
Units of Measurement: Per Mille and Karat
Fine gold content is expressed in two ways:
- Per mille (‰): International standard designation, also called the "thousandths stamp". 999 means 99.9 % gold, 585 means 58.5 % gold. This number is often stamped on bars and coins (fineness hallmark).
- Karat (kt): Traditional unit of measurement, mainly used in the jewellery trade. The scale runs from 1 to 24 karat, with 24 karat corresponding to pure gold (999.9 ‰).
The conversion between both units is straightforward:
Per mille = karat × (1000 ÷ 24)
Karat = per mille × (24 ÷ 1000)
Example: 18 karat × (1000 ÷ 24) = 750 ‰
Common Fine Gold Contents at a Glance
| Karat | Stamp | Fine Gold Content | Typical Use |
|---|---|---|---|
| 24 kt | 999 / 999.9 | 99.9 % / 99.99 % | Investment bars, investment coins |
| 22 kt | 916 | 91.6 % | Krugerrand, Sovereign (Crown Gold) |
| 21.6 kt | 900 | 90.0 % | Vreneli, Napoleon (Latin Monetary Union) |
| 18 kt | 750 | 75.0 % | High-quality jewellery |
| 14 kt | 585 | 58.5 % | Everyday and fashion jewellery |
| 9 kt | 375 | 37.5 % | Jewellery in UK/Ireland |
| 8 kt | 333 | 33.3 % | Most affordable gold jewellery (DE minimum) |
Fine Gold Content and Material Value
For valuation purposes, fine gold content is directly relevant: the melt value (also material value) is derived from the gross weight of a piece multiplied by the fine gold content and the current gold price. The melt value calculator enables this value to be determined in seconds.
The fine weight – i.e. the weight of the contained pure gold – is calculated as follows:
Fine Weight = Gross Weight × (Fine Gold Content ÷ 1000)
Example: 10 g × (585 ÷ 1000) = 5.85 g fine gold
Buyers and refineries always pay on the basis of fine weight. A piece of jewellery in 750 gold with a total weight of 20 g therefore contains 15 g of pure gold – the buying price is calculated for this fine weight. The buying price calculator shows the expected proceeds depending on fineness and weight.
Investment Gold: Special Purity Requirements
For tax-exempt investment gold within the meaning of the EU VAT Directive, minimum requirements apply:
- Bars: at least 995 ‰ fine gold content
- Coins: at least 900 ‰ fine gold content, legal tender in the country of origin
Classic investment bars from manufacturers such as Heraeus, PAMP Suisse, or Valcambi carry the stamp 999.9 (so-called "Four Nines"), which corresponds to the highest commercially customary level of purity. Technically, 999.99 (Five Nines) is possible, but is rarely seen in the investment segment.
Testing Fine Gold Content
Various methods are available for determining fine gold content:
- Hallmark check: Reading punches and fineness stamps on the piece (e.g. "750", "18K", "750/1000").
- Streak test: Abrasion on a touchstone with acid – a quick dealer method, though imprecise.
- Acid test: Reaction with nitric acid or aqua regia gives an indication of the content.
- X-ray fluorescence analysis (XRF): Non-destructive, highly accurate measurement of elemental content – standard among professional buyers.
- Density determination (Archimedes): Comparison of weight in air and water allows conclusions about alloy composition.
In Brief
Fine gold content is the central figure for every gold item: it links weight and gold price to produce the real material value. Anyone who knows the fineness can use the gold calculator to calculate the exact value of their gold at any time – whether jewellery, coin, or bar.