Discover amazing white color gel crayons that reveal their true colors on black paper only. Mystery Metallics Gel Crayons are smooth to draw with, leave a metallic sheen and quite frankly are amazing. The gel crayons are made with a waxy gel that appears white, but once you lay the gel crayon on black paper they leave a metallic sheen in 6 incredible colors including purple, red, gold, white, green and blue. You'll find that Mystery Metallics are amazingly smooth to color with and make a great artistic tool for kids and adults alike. They work on kraft paper too.