With Silk Clay, you can easily create colorful and fun figures or decorate objects made of glass, wood, or Styrofoam with imaginative designs. The rubbery, soft, and smooth modeling compound does not smudge, is health-safe, and hardens on its own while you let it dry for 2 to 24 hours, depending on the thickness. When stored in an airtight container, Silk Clay has a very long shelf life. Even if you forget to put the lid back on immediately after use, you can still use the compound. With a little water and some good kneading, you can restore its elasticity.