Beautiful, malleable, incorruptible, and with the colour of the life-giving Sun, gold has always been associated with purity and all things everlasting. It is no surprise that when made into the perfect circle it is used to represent the bond of marriage in the traditional wedding ring.
Pure gold is a beautiful rich yellow colour. It is very soft and so it is usually alloyed with other metals to give it hardness and sometimes a different colour. The purity of gold is given by its 'carat' (ct). This is the parts of gold by weight per twenty-four parts of total metal; i.e. 24 carat gold is pure gold, while 18 carat gold is 18/24 = 3/4 or 75% gold by weight. The higher the carat the more valuable the metal.
The purest gold routinely used in jewellery is 22 ct; 18 ct and 9 ct are popular in Britain and Europe; 14 ct is popular in Canada and the USA.