Only ET likes green fingers. If a ring turns your finger green or black, this is caused by a reaction between the chemicals in your skin or sweat and the metals in the jewelry. This happens most often with rings, but can also be a problem with a bracelet, watch or necklace.
The green or black stain doesn’t necessarily mean you are wearing cheap jewelry. Gold or sterling jewelry is made with an alloy of metals partly because pure gold or pure silver is too soft to hold its shape for satisfactory wear. Sterling silver is 92.5% silver and 7.5% copper. If a sterling silver ring turns your finger green, that is from the copper in the ring.
Sometimes a piece of jewelry is not properly pickled after soldering, and this results in a thin coating of copper. The copper reacts very readily with perspiration to form the green oxidation stain. To remove the layer of copper, soak the ring in a 50/50 solution of ammonia and water for 24 hours. The liquid will turn light blue as the copper is removed from the ring. This will not harm the silver. Then rinse, dry and apply a thin coating of sealer to prevent the stain from returning. A thin coating of clear nail polish could also be used, but will not last as long as the jewelry sealer.
Black stains are also caused by oxidation. Clean the jewelry as above and coat with sealer. Wait a day before wearing the piece again
If the problem occurs with earrings, try using a plastic post cover, sold at jewelry supply stores. This solution may also work for people with a mild allergy to nickel that causes some discomfort after wearing earrings for a number of hours.
Once the jewelry is cleaned and sealed, remove the stain with a paste made from a teaspoon of baking soda and water. Leave the paste on your skin for about ten minutes, then wash off with mild soap. Repeat as necessary.
An allergy to metals (nickel is often the problem here) is a different story. This will cause redness, swelling, and sometimes a rash. With more severe allergies, the skin may blister or crack. If that occurs, see your doctor to prevent an infection. A dermatologist can confirm metal allergies by using a skin prick test.
Green or black stains are most likely to occur with rings than with other jewelry because they fit snugly and your hands sweat. Whatever the cause, following these simple tips should help you avoid or clear up the green or black stains caused by rings.
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