The growing popularity of Rose Gold or Pink Gold is undeniable. But few people really know what rose gold is. Rose gold is often referred to as pink gold or red gold. During ancient times, impurities that were a result of the smelting process often caused gold to turn a reddish color. This is why many Greco-Roman texts, and even many texts from the Middle Ages, described gold as "red." Rose Gold gets its red color from its conglomeration of pure gold and copper alloy.
The higher the copper content, the redder the gold so the terms red gold, rose gold and pink gold is often used to differentiate the amount of red, or copper, in the gold. If the rose gold is used in a piece of fine jewelry it will be made of 18 Karat gold. Eighteen karat red gold may be made of 25% copper and 75% gold. For 18 karat rose gold, usually about 4% silver is added to 75% gold and 21% copper to give a rose color.