The colour of gold varies according to its purity. Absolutely pure gold is measured as 24 carat, but because at this purity it is too soft for jewellery intended to be durable, it is mixed with other metals. Yellow gold contains 53% gold, 25% silver and 22% copper.
Did you know?
- A 50th wedding anniversary is known as the golden anniversary.
- The legend of the golden fleece may be a reference to the use in antiquity of fleeces to collect gold dust from alluvial deposits.
- In the Middle Ages, the nobility sometimes used gold flake as a food decoration to demonstrate their wealth or because they believed that such a valuable material must also have health benefits. Gold leaf is still used in foods and some cocktails contain flakes of gold.
- Gold is also used for making solar cells on spacecraft and helmets for moon walkers, as it can store the sun’s energy. It is also used in dentistry, medicine and computers.