click here for a quote. Additional information. Weight. 100 lbs.Foundry sand and water click here for a quote. Additional information. Weight. 100 lbs.About Green Diamond Molding Sand. Green Diamond Foundry Sand is available in ferrous and non-ferrous foundry grade sands and is the ideal silica free replacement for olivine and silica sands for molding and coremaking. Greater Durability Than Both Olivine and Western Silica Sands. Lower Pouring Temperatures. Can Be Pre-Mulled with Clay Additives.Plaster/Silica Mixtures for Mold Making. The traditional mold material used for kiln casting is a 50/50 mixture of plaster and ground silica. This produces a mold that is inexpensive and will work fairly well for small projects. For larger items it's often better to reinforce the plaster/silica or even use an investment other than plaster/silica.Silica is one of the cornerstone materials of glaze and claybody formulation. Although this mineral is present in many different ceramic materials (from feldspars to bentonite to sand,