Fineness in precious metals is the measure of purity. Fineness is usually given as a number, with the higher numbers indicating greater purity (e.g., 999). Fineness can be used to describe alloys of gold, silver, and platinum, but it's most often associated with gold fineness that gives a good indication of the type of gold you have on your hands.
Fineness has two components: firstly, how pure an alloy is; secondly, the total weight percentage of impurities contained in that alloy (i.e., what proportion of its mass consists of other materials). Fineness does not indicate whether an item contains any non-precious metals such as copper or nickel - these are generally indicated separately on packaging labels.
Fineness can be expressed as a decimal (e.g., .999) or percentage (e.g., 999%), and it represents the number of parts per thousand, so if an item has fineness .9999, then there are 990 parts out of 1000 that are pure gold. Fineness marks also signify how much silver, copper, palladium, or other metal alloying agents were added to the gold during the manufacturing process.
When it comes to precious metals like physical gold, fineness is king! The higher the number, the purer the metal and the less likely it will corrode or tarnish over time.
So whether you're in the market for an investment-grade item or simply looking for a beautiful piece of jewelry, make sure to check the fineness before making your purchase. When it comes to investments, paper gold does not consider the fineness so it's unnecessary to consider.
Fineness is verified by X-ray fluorescence or by an electronic device that calculates the amount of precious metal contained in a piece.
The most common gold fineness is 999.999 (~99.90% pure). Other purities include 333 and 22, which indicate a silver alloy (33/22 = ~75% pure) and the proportion of other metals in the alloy, respectively.
More than 999-level purity can be achieved by adding more or alloys with non-precious metals such as copper or nickel to change its color from yellow to red or white.
These are known as rose & white golds, respectively, typically known as rose & white golds containing 75%-85% precious metal content each.
Finer purity levels may also be available for order, but they're usually reserved only for large commercial orders - sometimes even going up to 999.9999 (~99.9998% pure).
Gold Fineness 999.999 to 333
1. 999.999: The purest gold ever produced, refined by the Perth Mint in 1957.
2. 999.99: The most popular purity for everyday coins such as Canadian Gold Maple Leaf and American Buffalo coins.
3. 999.9: Fineness used by the Royal Canadian Mint for commemorative coins.
4. 999: Fineness of Chinese Gold Panda Coins
5. 995: Fineness is required to be accepted in Good Delivery bars (the purest type of gold currently produced).
6. 990: Two nines fine, mainly alloyed with silver and copper, sometimes known as "coin" gold or crowns.
7. 986: Ducat fineness was popular during the Renaissance time from 14th to 16th century among Venetian traders who considered it a good trade coin that could buy three times its weight in fine silver. Finer than 24 carats (.9995) are referred to as 21 carats / 18 carats e.g., 999.
8. 958.3: 23 karat gold, the purity of British Sovereigns and South African Krugerrands.
9. 916: Crown gold. The fineness was historically used for the most widely traded bullion coins, e.g., American Eagle Gold Coins from 1795–1833.
10. 900: one nine fine, fineness used by the United States Mint for 1837 to 1933; currently used in Latin Monetary Union mintage (e.g., French and Swiss "Napoleon coin" 20 francs).
11. 899: American Eagles briefly for 1834-1836.
12. 833: 20 karat gold, fineness found on some European jewelry items.
13. 750: 18 karat - In Spain, "oro de primera ley" (first law gold) is a common designation meaning 75% pure or better. Often seen as ".750" on markings. Finer than 18 carats are referred to as 21 carats, 22 carats etc. (e.g., 999.75).
14. 625: 15 karat.
15. 583.33: 14 karat - In Spain, "oro de segunda ley" (second law gold) is a common designation meaning 58.33% pure or better, often seen as ".583".
16. 417: Fineness used in Mexico for some older coins; also British Trade Dollars of 1873-1878 and certain Australian coins.
17. 375: Fineness used by the United States Mint on half eagles from 1795 to 1933.
18. 333: Minimum standard for gold in Germany after