Developed by Sennellier & Pablo Picasso, Sennelier Artists Oil Pastels contain more pigment than any other brand. Use on a variety of surfaces including canvas, paper, metal, wood, stone, even glass. Create multi-media effects over oil, acrylic, pastel or watercolor. These pastels can be thinned with turpentine are lightfast non-toxic and acid-free to resist drying. Choose from 120 open stock colors. WARNING: This product contains a chemical known to the state of California to cause cancer. (Unbound Titanium Dioxide)