Why is there a color difference between some gold coins?
Individuals who have observed bullion and proof gold coins often ask this question. It is also sometimes observable in bullion coins of different dates. The question of color then stems from the premise that gold is gold and the color should be exactly the same. Although the last sentence is factually correct the premise of judgment of color is incorrect. The reason for this is that the Krugerrand coin, is not pure gold but 22 carats. This amounts to approximately 91.6% gold. The rest of the coin is then a mixture with another metal usually for hardening reasons. One metal mixed or better put, melted with one or more other metals is called an alloy. The Krugerrand coin is essentially a gold alloy where 91.6% of the coin is gold. The other 8.4% is another metal, which can differ from year to year and coin to coin. The coin alloy is often composed of gold and either copper, brass, titanium or zinc. Depending on the choice for a mixture of gold, the actual color and size of the coin by we
