Gold and Gold Alloys
Some people find that they are allergic to the nickel. If allergic, the location under the ring or bracelet, for instance, will turn a black color or raised blisters will appear. Taking the jewelry off over a short period of time will cause the black to disappear and allow the blisters to heal. Because of allergic reactions, it is a good idea to wear platinum instead if it fits in your budget.
Platinum comes out of the ground as a pure white metal and no one is allergic to it. Rose and Pink Alloys Copper is the alloy used to turn yellow gold to rose or pink gold. The more copper used, the more intense the rose color it becomes. Green Gold Alloys Silver added to yellow gold will turn to green gold.