Many customers have asked us why copper bracelets have residues on the skin after wearing them for a long time. The most common residue is patina. Now I am here to answer for you.
Copper is a naturally occurring element on the earth, so it needs to be refined into a metal worn as jewelry. The ability of copper to conduct electricity with minimal energy loss makes this copper extremely valuable. Because the body is easy to oxidize, when exposed to other chemical substances or external elements (even simple chemical elements like oxygen), copper can easily react, causing its surface to change.
The oxidation reaction of copper with oxygen and moisture is completely harmless. This is because of the way that nature deposits minerals on the skin. The speed of occurrence depends on the pH balance of the skin, which does not affect the function of the bracelet.
The acidic nature of human sweat and other chemicals on the skin (such as soaps, lotions and cosmetics) also react with copper. This reaction will result in the formation of a green patina or surface coating on the copper surface, because the skin is in contact with the copper and the color will be transferred to the skin. The reaction varies depending on the individual's chemistry, including how long it takes for the green discoloration to form and how obvious the color becomes. Some people may not have any discoloration at all.