As I mentioned, gold is a relatively soft metal, so high-karat stuff are often easily damaged. A 24 karat item is generally reserved for display or ceremonial use. In the stores, most gold items have a karat rating in the range 9 to 18. In the US, the minimum karat value for gold jewelry to be sold is 10, but in the UK 9 karat is more common. In additional, gold purity does not affect its weight! Different color of gold are mixed with different other metals. For example, gold mixes copper is called red karat gold.