How do I care for my molds CLEANING: After repeated use or when too little cornstarch is used, the molds can develop a sticky residue of plasticizer from the clay. When molding a dark-colored clay, sometimes you can see the residual color left in the mold. With light clays it is harder to detect the residue, but it's often there. Molds can be cleaned with waterless hand cleaner or rubbing alcohol and a soft toothbrush. Make sure the mold is thoroughly dry before using it again. Firm clay should release well from a clean mold. When the clay starts sticking, it is a signal that it is time to clean the mold. DURABILITY: To ensure that your mold will be long-lasting, always use your molds on a flat surface only. Pressing clay or other substance into your mold in your hand instead of on a hard surface will make your mold weak and shorten the life of your molds. KILN: Molds are not to be used in a kiln, but can be removed from the mold prior to curing in the kiln. If you take care of your molds they will last a very long time!