All gold in its natural state, is yellow, however by alloying it, with other metals, the colour can be altered to some extent.
ROSE GOLD, popularly used in the late Victorian and Edwardian jewellery, is yellow gold alloyed with COPPER and SILVER, giving its slightly rose-pink colour. The higher copper content however tends to make the gold hard and brittle.
WHITE GOLD, introduced early in the 20th Century, and frequently used in modern jewellery, White Gold is made by alloying yellow gold with other white metals, principally PALLADIUM and SILVER, diluting the colour to a very pale yellow. Compared with platinum, white gold is a lighter weight, and is therfore a less costly metal. It is much easier to use, so has a lower manufacturing cost, and therefore is an economic alternative to the harder, and more expensive, platinum.
RHODIUM PLATING WHITE GOLD
Usually, as the last process, white gold jewellery is electroplated with Rhodium, a metal similar to platinum, to achieve a bright white surface finish. Although very hard, rhodium plate will eventually wear through, but can be easily re-plated. (See Services Available) White gold is particularly useful in earrings and pendants where the wear is minimal.
GREEN GOLD, the least frequently seen colour, is achieved by adding silver alone as the alloy, creating a yellow metal with a slight greenish hue.