22 Carat Gold or 24 Carat Gold Coins?

Different Spelling, Same Concept

The spelling of the word "carat" varies based on location. In the United Kingdom and most of the world, the spelling used is "carat", while the United States uses "karat". However, when referring to gemstones, the US commonly employs the spelling "carat". The abbreviations commonly used for carat include 24kt, 22-ct, 22k, and 24-k.

Carat: A Measurement of Gold Purity

Carat is a unit of measurement used to determine the proportion of gold purity in an alloy. The ratio of pure gold is calculated by using 24 parts as a whole, with one carat being equal to 1/24th of the whole and 22 carats being equal to 22/24 parts of the whole.

Fineness: Another Measure of Purity

Fineness is another term used to describe the purity of gold and is calculated as a fraction of a thousandth of the whole. Regardless of whether the fineness is expressed as 999, 99.9, or 0.999, they all denote the same quantity of 999 thousandths of pure gold and one part of a base metal.

You will often see coins being described in both carat and fineness:

Comparing 22 Carat and 24 Carat Gold

Gold coins with a purity of 22 carats contain .916 gold, with the remaining .084 being comprised of a base metal such as copper, silver, zinc, or nickel. Conversely, 24-carat gold coins contain .999 gold, with the remaining .001 being comprised of a base metal that is often difficult to identify.

For example:

Krugerrand contains 1 troy ounce of gold = 31.1035g

31.1035g   divided by   weight of coin 33.9305g   =   0.916 fineness   x 24   =   22 carat

We should note that it is almost impossible economically or commercially to obtain absolutely pure gold. Before electrolytic refining, highly refined gold is usually .9995 pure (99.95%). If we convert this to carats, it would be 23.988 carats. London Good Delivery Gold Bars are acceptable at .995 which is "only" 23.88 carats. With electrolytic refining, it became commercially and economically possible to produce .9999 fine gold, which works out to 23.9976 carats. The Royal Canadian Mint also produces a .99999 fine gold coin, advertised as the world's purest gold coin. This works out at 23.99976 carats. It follows from this, that it is more accurate to refer to these coins by their millesimal fineness rather than as 24-carats.

22 Carat Gold Coins: A Timeless Tradition

22 carat gold coins have been in circulation for thousands of years and were often made to .916 fineness or .900 fineness, depending on whether the coinage system was influenced by British or European standards. Coins made from 22-carat gold are stronger than those made from pure gold, as the addition of other metals creates a durable coin that is resistant to tarnishing and damage. Coins struck in 22 carat gold include the Krugerrand, modern American Eagles, Sovereigns, and Britannias (1997-2012).

Coins which are struck in 22 carat gold include Krugerrands, modern American Eagles, Sovereigns, Britannias 1997-2012

24 Carat Gold Coins: A Modern Masterpiece

In the 1980s, several mints began to issue 24-carat gold coins due to the perception that these coins were of higher quality than those made from 22-carat gold. The Royal Canadian Mint took this a step further by producing the 99999 Maples, which are considered to be the purest gold coins available. Despite this, the 99999 Maples still contain a minuscule amount of base metal that prevents it from being pure gold. Even though the 99999 Maple is classed as 24-carat gold, we have still seen coins with red spots** on them.

Coins that are struck in 24-carat gold include Maples, Pandas, Perth Mint’s Lunar and Kangaroo/Nugget coins, Philharmonics,  Britannias (2013 to now), Queen's Beasts and British Lunar.

**Red spot is a natural process where the alloy oxidises and forms small reddish marks on the surface of the coin. We do not feel that this detracts from the value of the coin. Read more about red spot here.

How Much Gold In A One Ounce Coin?

Watch our video on how to measure the gold content of a 1-ounce gold coin.