One very important feature about gold is that it is a traditional metal and only very important objects are made out of it. Pure gold is not hard enough to

be able to stand up to the stress that a lot of jewelers need to apply to make jewelry therefore gold is alloyed with other metals like that of silver,

copper and platinum as this helps to maintain its durability and therefore almost all the gold that is utilized in making jewelry is an alloy of gold with

another or other metals. The alloys of gold do not have as high a value per unit of weight as pure gold does. There is a standard of trade that is more

commonly known as karatage that was established to allocate the gold content of the alloys. If you have a gold necklace or ring you will probably have

noticed that it is marked with a number and a “K”. Pure gold is known as 24 karat gold and is usually marked with “24K”.

Read more at: http://pennyomega.com/?p=16628