Due to a lack of any available epoxy tooling gelcoats where I live, I have started making my own using laminating resin and a variety of fillers and additives. I like to add a black pigment, as the black makes it really easy to find low spots and polish to a great shine, however my issue is that most of the fillers I use are a white powder, so instead of a nice solid black gelcoat I end up with a sort of gunmetal grey.