Gold, in its purest form, has a characteristic bright golden yellow colour. However, due to the high purity of gold, it is not feasible to use pure gold for making jewellery. Therefore, it is combined with other metals, such as copper, silver, palladium, etc., to increase its strength. The colour of the gold is determined by the metal with which it is combined.

The mixture of pure gold and copper results in the formation of rose gold. The difference between rose gold and pink gold lies in the usage of copper. By carefully changing the proportion of copper in the mixture rose gold and pink gold can be obtained. Pink gold comes under the varieties of rose gold. What the colour shade of rose gold is, depends upon the percentage of copper used in the overall alloy. Less amount of copper will be used to obtain a light shade of pink. For a higher grading of pink, high amount of copper will be used to achieve the desired colour. 18 karat rose gold consists of 75 per cent of gold, 22.5 per cent of copper and 2.75 per cent of silver, while 18 karat pink gold consists of 75 per cent of gold 20 per cent of copper and 5 per cent of silver.