Lava For irregular grain, color to red to brown and black, porous light,and it's the good filter material. Lava ... as follows:Chemical composition SiO2 CaO MgO Fe2O3 FeO Al2O3 TiO2 K2O Na2O6,Founction: It is suitable for various filter, ion ... dyeing, petroleum, chemical industry is the ideal product. Lava (Brown, black, red)