The R&F Pigment Stick, 38ml in Iridescent Copper is the iridescent version of Mars Red. R&F Pigment Sticks are seductively soft oil paints in stick form, providing today's artist with a truly direct way to work. They contain no dryers, no fillers or adulterants and no expedients of any kind. Because we do not use shortcuts, the wonderful workability of our Pigment Sticks depends on a very careful balance of oil, waxes and pigment. Iridescent Copper stick consists of metal oxides on mica.