I think you're right Tink, "plated" falls within the spectrum of costume or fashion jewellery. The problem comes if your plated item doesn't agree with your body chemistry and tarnishes or otherwise changes colour. I have a beautiful hexagonal amethyst bezel set ring in silver plated base metal (possibly brass) once the silver started to tarnish any attempt to clean it took off more of the silver. Finally the ring lost all its silver so I used the QVC silver and gold plating kit (circa 1996) firstly adding a coat of silver and then gold plating it with the help of my microwave. To this day it still looks like 9ct gold. When I was executor for my mum's will I had all her jewellery valued so I could split the value with my siblings and was surprised to find her gold bangle, worn every day for about 20 years was rolled gold but, as it had no real value it meant I could keep it and I wear it often. It doesn't matter what it's made of, if you value it then that's what matters I reckon.