Ring turns finger green

"Copper(II) acetate is soluble in alcohol and water and slightly soluble in ether and glycerol. It melts at 115 °C (239 °F) and decomposes at 240 °C (464 °F). It can be prepared by reacting copper(II) oxide, CuO, or copper(II) carbonate, CuCO3, with acetic acid, CH3COOH. … "

"…Propionic acid (propanoic acid) is commonly found in sweat - propionibacteria break amino acids down into propionic acid. Propionibacteria live in the ducts of the sebaceous glands of adult and adolescent humans. Some people may identify a vinegar-like smell with propionic acid, because it is similar to acetic acid, which gives vinegar its sour taste and pungent smell.

Anyway, need to clean the offending item …LoL Funnily enough a vinegar and salt scrub will clean the verdigris / oxidation off the metal.

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