Multi-ply black organic rubber was always the molding material of choice for producing highly intricate castings in tin and lead alloys. Now that the black organic rubber is not available, at least temporarily, our friends at Nicem® have formulated a new silicone rubber with the same or better physical properties than the organic rubber. Nicem® Black Ultra-High Tear Silicone is a genuine breakthrough in silicone technology and is by far the best alternative to black organic rubber. Like all Nicem silicones, Nicem® Black Ultra-High Tear Silicone is formulated and blended using only the highest quality polymers and fillers.

Every silicone rubber mold set has a nominal thickness of 1" and consists of four 1⁄4" thick sections. The term "durometer" used in the table below refers to the relative hardness of a rubber compound when cured. The higher the durometer, the harder the rubber compound is.