These metal powders are used in resins to create cold cast metal effects (which can then be patina'd like real metal) to create a realistic finish which can be polished with steel wool and buffed to a shine.
Metal powders are added at user discretion, every project is different and can be added to each specific application to give the desired metal effect.
As an approximate guide the minimum ratio would be a 1:1 mix for the metal powders, for every 100g of metal powder to every 100g of resin, depending on casting requirements this could be increased up to 4 parts metal powder to 1 part resin by weight.
We advise dusting a light layer before creating your resin/metal mix to achieve the best finish possible. Different powders can be mixed together but make sure the powders are premixed before adding to the resin.