You’ve got one of these, I know I have tucked away in a jewellery box. A ring you loved, bought while you were having fun and the sun was shining, on a whim because you liked it but when you tried to wear the ring, it just turned your finger green, so disappointing! What can you do? Well, there’s a simple reason why it happens and a simple way to solve the problem.
Why Your Finger Goes Green in the First Place
This is because there is copper in the ring. Most metals used in jewellery are alloys which means they are not one metal but a mix of metals. Everything from gold and silver via bronze and aluminium to exotic alloys like Inconel (used in F1 exhaust pipes due to its extreme heat resistance) are alloyed or mixed with other metals to improve or change them. Whether your finger goes green or not depends how much copper is in the ring and how it reacts with the salt and moisture on your skin. The green is verdigris, a naturally occurring copper patina. You will have seen it on architectural metal such as Goodwood House roof and sculptures such as the Statue of Liberty.
Gold and Gold Coloured Alloys
Jewellers do not often use pure gold or 24-carat gold. You will find it more often in investment bullion. It is dark yellow, but it is too soft to make very durable objects, it scratches easily during everyday wear, the same is true of 22-carat gold, which is used more often in pieces that will not rub against anything such as brooches. Gold is mixed with silver and copper in varying amounts to make different carats of yellow gold. 18 carat gold is 75% pure gold, 14 carat 58.5%, and 9 carat 37.5%. The chances of a 9-carat gold ring turning your finger green are higher than that of an 18-carat gold ring. I’ve never come across a 9-carat gold ring doing this but let me know in the comments if this has happened to you!
This is a fantastic metal for jewellery because it casts beautifully and wears well, unfortunately, because bronze is an alloy heavily based on copper it will turn your finger green. It is a mix of copper and tin and is one of the longest used alloys known to man. There are many modern types of bronze alloy for various uses, but the essential base of copper has remained unchanged for millennia. These fibulae brooches photographed in my local museum are bronze, and you can see how green they have gone with age.
Brass is another gold coloured alloy that will turn your finger green, like bronze it is based on copper, this time mixed with zinc. It is a much brighter gold colour than bronze but is similar in the way it wears.
Silver and Silver Coloured Alloys
Silver won’t turn your finger green, again it is the copper that it is alloyed with that will if the alloy is not of a high enough silver content. The most commonly used alloy is sterling silver, so called because it used to be used in coins and until 1920 silver coins in the UK were made from sterling silver, after that to 1946 they were 50% silver. Sterling silver is 92.5% silver the rest is copper. At this level, your finger will not turn green even down at the lower fineness of 80% silver you are safe. It is when you have unknown alloys full of copper and nickel, and goodness knows what else that the trouble happens. A green finger is the least of your worries here. Nickel can cause a skin reaction in some people.
How To Fix It
- For precious metals always check the quality you are buying. In the UK the hallmark is your protection here, not just a 925 stamp which is pretty much meaningless. All precious metals offered for sale in the UK and described as such must be hallmarked, even imported jewellery. It should have a minimum of three stamped marks. 1) The initials of the maker, 2) a fineness mark which is a number that confirms the alloy, 3) the mark of the assay office that tested and marked the item. It may also have 4) a traditional fineness mark and 5) a date letter stamp.
- Bronze and Brass, do nothing. It’s harmless and do you really care that your finger is a bit green? The bronze and brass rings I have stopped turning my finger so green after a while. The reaction seems to slow with wear.
- You really hate the fact you’ve got a green finger but still love the ring? The most straightforward and cheapest option is to carefully paint some clear nail polish as a lacquer on the inside, and up the outside a little way, this blocks the connection between skin and metal so the reaction can not happen
- wear the ring as a pendant on a long chain over clothes in the winter, no contact with skin no green stain.
I hope this helps you to keep on enjoying your jewellery and helps you make better jewellery buying decisions in the future, any queries, comments questions or observations put them in the comments below. I’d love to hear your thoughts and stories.