Pure copper characteristics: Copper jewelry is popular because it looks good and has some physical therapy benefits. However, after wearing it for a period of time, you may find that the skin underneath turns green. This is a normal reaction that will happen to any copper in contact with the skin for a long time, and will return to normal after you stop wearing copper jewelry, and will not bring health hazards. 1.Tibetan 100% Pure Raw Copper healing rings are great for finger joint pain and swelling. The copper helps relieve tendon pain and improves circulation. 2.For those unfamiliar with wearing copper jewelry, copper always tarnished and always marks the skin to a certain extent. The amount depends on several factors, such as how acidic your skin is and how much you perspire. Thats the property of pure copper. 3.However if you are concerned about the stains caused in your finger by this ring you can clean the ring to remove the tarnish and then paint it with clear nail polish or regular topcoat. 4.We at recommend not to apply any polishing and wear it as is for ring to work properly for Healing purpose. You can always wash your finger with mild soap and warm water to get the stain off.