Below are some advantages of getting a 1-carat diamond ring yellow gold. Pure gold is not used for engagement rings for the simple reason that it is too soft, causing it to scratch, mar, or get damaged in some other way. What you see in the market instead is 18 karat and 14 karats yellow gold for engagement rings. These are technically alloys, containing more than just one metal in them. Copper is one of these alloys, and is found in the well known rose gold. Alloys may differ among brands, which is why you will also notice a slight color difference if you check out the same karat band at two different stores. If you notice different shades of yellow, it is not just your imagination. Yellow gold is a good way to save money because the cost of the diamond will go down. You can get a near colorless diamond and it would look perfectly colorless on a yellow gold band.