Here is another kind of artist palette. This one is in the traditional palette shape, with the thumbhole for easy holding. It's made of white plastic and contains a number of small convex "mixing wells". If you normally mix small (really small) amounts of color each time, and want to keep them separate from each other, then this palette might work well for you.
Because it's plastic, you do need to be careful about not letting the paints dry on the palette, as it can be difficult to clean after the paint has hardened. A thorough wash after use should be fine!.