Pre-mixed and ready to add your Black Sands, Ore, Gold, Silver, Computer Parts, Scrap Gold and smelt. Used not only for Gold, but also as Silver smelting flux or in a combination of both. Helps draw out impurities by bringing them to the surface. A great assay mix. Includes Borax, Soda Ash, Silica & Manganese. Not recommended for Microwave smelting. too thick.