Gold is the world's most precious metal for several good reasons, among which is the sheer difficulty in producing it. Today most of the world's gold is found and produced in South Africa , though Australia , the U.S, China , Canada , Russia , Indonesia and Peru are also sources for gold. Despite being almost everywhere on the planet, gold is very difficult to extract and the process for finding it, extracting it and purifying it all cost money. On the other hand, it's also a material incredibly suited to making jewelry because it is very pliable and soft and doesn't erode or rust with time. It is relatively light and can be worn easily and comfortably throughout the day in rings, necklaces and especially earrings. This has given gold the supreme place as the best and most popular metal around and the range of varieties, colors and styles that it comes in today has secured this high station. It is, however, almost too soft for jewelry purposes, and for this reason gold is combined with other metals to strengthen it for durability and wear. Pure gold is also far too expensive for most people to afford and mixing it with other metals reduces cost tremendously. This mixture of metals is called ‘ alloy' and today you would be hard pressed to find any piece of modern jewelry made of one pure metal. All jewelry is made of alloys today. The amount of gold in relation to the whole weight of the piece is called ‘ fineness' , and this is an important thing to ask when buying any gold jewelry. The metals mixed with gold to create different alloys are zinc, copper, silver, nickel, palladium and platinum.