I would like to use cold enamel in silver but read in Kathie Murphy's "Resin Jewellery" that both the resin and the silver may discolour over time unless the silver is protected. No solution is offered so does anyone know any more about this? Would fine silver have the same effect? Is there something I should paint on first that won't react with either the silver or the cold enamel (Cookson's brand). Any advice welcome!