I have too many palettes. The good thing is that with one exception, I’ve made them myself, so they hardly cost anything. I spray the inside with white enamel paint to give a good mixing area.
This one is a standard Altoid tin. I’m fairly certain this is Cathy Johnson‘s idea but I can’t find it in her blog (her personal web sites seem to be down right now). Add an extra bottom to make more mixing area. I tried clipping it together to make one unit that can attach to the sketchbook.
This is a new, empty tin I got for $4.82 at the Daniel Smith mothership (Main store on 1st Ave in Seattle). It holds 18 half pans with room for a couple brushes. It is 7.25 x 2 inches.