How to read fineness and markings on investment gold
On every investment bar and coin you will find a series of numbers, abbreviations and marks. What do they mean and how do you read them correctly? In this guide we explain fineness, weight, maker's marks, hallmark and serial number – so you know exactly what you are holding.
Fineness: what 999.9/1000 means
Fineness indicates how much of the item is pure gold. The marking 999.9/1000 means that out of 1000 parts, 999.9 parts are pure gold (Au) – that is 99.99 %. This highest common standard is called „four nines". For investment gold, 999.9/1000 is the standard today; some older coins have a lower fineness (e.g. 916.7 – an alloy for greater durability).
Fineness in karats
A second way of writing it is karats (abbreviated kt or K). Pure gold is 24 karats. The conversion is simple:
- 24 kt = 999/1000 and higher (pure gold),
- 22 kt = 916.7/1000 (e.g. historical coins),
- 18 kt = 750/1000 (mostly jewellery).
Note – do not confuse karats (fineness) with carats for gemstones, where it refers to weight.
Weight and units
Weight is given in grams (g) or troy ounces (oz). One troy ounce = 31.1 g. This unit is standard in the international precious metals trade.
Markings on a bar
An investment gold bar usually carries the following details:
- logo and name of the manufacturer (e.g. Argor-Heraeus, PAMP, Valcambi),
- weight (e.g. 10 g),
- fineness (e.g. Fine Gold 999.9),
- chemical symbol of the metal – Au (gold),
- serial number on smaller minted bars in a blister.
Markings on a coin
On an investment coin you read different details:
- face value (the coin is legal tender – the exception is the Krugerrand with no face value),
- year of minting (year of issue),
- weight and fineness (often struck directly into the coin),
- design and series name (e.g. Wiener Philharmoniker, Britannia),
- mint mark – a small symbol of the mint.
Hallmark and authenticity marks
A hallmark is an official mark confirming fineness; the practice varies by country. With investment gold you mostly encounter the fineness struck directly by the refinery or mint; an official hallmark is more common on jewellery. In any case, the credibility of the details rests on the manufacturer's reputation and verifiable origin.
Certificate and serial number
Minted bars are often sealed in a blister with a certificate that repeats the weight, fineness and a unique serial number matching the bar. Keep the blister and certificate – they support future tradability.
Frequently asked questions
What does 999.9 on a bar mean?
That the product contains 99.99 % pure gold – the highest common fineness standard, known as four nines.
Is 24 karats the same as 999.9?
Practically yes. 24 karats denotes pure gold; in precise fineness notation that corresponds to 999/1000 and higher (for investment gold usually 999.9).
Does investment gold have to have a serial number?
Minted bars in a blister usually have a serial number matching the certificate. Coins and cast bars need not have one – their authenticity is assessed by the strike, weight and origin.
Conclusion
Reading the details on investment gold is easier than it looks: fineness (999.9/1000), weight (g/oz), manufacturer, plus face value and year on coins. Once you understand these marks, you compare products more easily and know what you are buying. Browse the offer of investment gold at GOLDU – all new, with verified origin and original packaging.
Disclaimer
This article is for informational and educational purposes and does not constitute investment or tax advice. More in the document Risk disclosure.
