Why does jewellery sometimes blacken the skin or clothing ?
Discoloration I blackening of the skin or clothes by items of jewellery causes doubts about the quality of the piece. Knowledge as to why this happens should help to dispel fears and may even suggest simple solutions. This data sheet attempts to explain how these effects may occur and how they can be overcome. There are two fT)aiQ\~~4~!~ of ,bi,$ form of discoloration : 1. Metallic Abrasion’ ,’. 2. Corrosion 1. Metallic Abrasion All metal can wear by: a. Constant rubbing against itself i.e.links in a chain, swivels. b. Rubbing against other hard substances i.e. talc -a very hard, fine powder. The jewellery is not abraded by rubbing against the skin or clothing as neither is harder than the metal. However, the skin and clothes can carry hard particles from cosmetics, face and body powders, stiffeners/fillers in modern textiles, talc etc. The particles abraded from the chain appear black because they are so finely divided, and a small amount of abraded metal creates a large amount of dus
