Dry Pigments

This painting was done a few week ago. It was one of the first times that I had used dry pigments mixed into the molten wax. I'd been using oil paint mixed added to the wax, with mixed results. The effects are okay, and the range of colours available is great, but I don't seem to be able to mix decent quantities because the oils settle to the bottom of the molten wax, and after a week or so, they go gritty at the bottom of the tin. I decided to try buying some dry pigments and experimenting with those instead, especially for black and white, which seem to be my staple with the encaustics. Unfortunately it seems that some of the pigments are reacting in the more or less the same way when left for any length of time. I'll have to keep tinkering. Perhaps I should buy some ready mixed waxes?