Why do I say composition? Because many of these items, if they are vintage, are made from a type of hard plastic or even a vinyl-type soft plastic you don't see a lot of any more. Some may be a soft form of resin, few are acrylic. The white and cream clusters are made from vintage molds and can be sponged with color beautifully. I love colorizing them and giving them my very own designer color and look. If they are colored already, you may be able to tinge the edges with metallic by using Gilder's Paste or even Smooch inks. If you do that, you will have to seal the color with matte spray lacquer. Be sure the color is CURED and spray VERY LIGHTLY.