Rose gold, which is used in diamond ring bands, is an alloy of copper and pure gold and is the reason for its color. The more the rose color, the more it has copper content in it. However, there is no pure rose gold although some may use the term when selling diamond rings. Instead, there are mainly two varieties of rose gold – pink gold and red gold. Pink gold has a light hue due to less copper content in it. On the other hand, red gold has a high content of copper, and hence, has a more red color to it. When it comes to karats, you can get the rose gold in same karats as that of a regular gold. Regardless of the color, the karat always refers to the gold content in a jewelry piece. For instance, a 12 karat yellow gold and a 12 karat rose gold diamond wedding rings will have the same purity.