Some people experience their finger changing colour while they are wearing a gold ring. If this happens to you, do not panic because it is relatively common and usually is harmless. The common belief is that finger discolouration occurs only when people wear sterling silver or other cheaper quality metals. However, discolouring of the skin is not always a reflection of metal quality and can occur in higher quality metals, such as gold. There are a couple of different reasons explaining why this phenomenon occurs. One explanation is that you are experiencing a chemical reaction, from the metal of your ring and the acids in your skin. The change in colour is a product of oxidation between your skin and the metal of your jewelry. Another possibility could be metallic abrasion from make up on your skin. Elements from cosmetic products can wear off particles from the metal, leaving a dark smudge on your finger. Some preventative measures include taking your ring off before applying makeup and then washing your hands with soap and water before putting your ring back on. Some experts suggest that discolouring can occur if your body is having an allergic reaction to certain alloys in the metal. Regardless of the cause, a simple solution to discolouration from your ring is to rhodium plate your jewelry to essentially add another protective layer between the alloys in your ring and your skin.