Creativity Street® Tempera cakes are an economical source of brilliant, opaque, non-toxic tempera paint. Just wet with water. For a bright velvet texture, brush on any surface (even glass). No more messy spills! When colors are mixed directly on the blocks, simply rinse with water for a fresh new surface of pure color. Each tempera block is 2-1/4" in diameter and 3/4" thick. One tempera block will cover more than 16 ounces of liquid tempera. Each set includes 6 tempera cakes: Red, Yellow, Blue, Green, White and Black.