silica in stone crusher used sand making stone quarry
How sand is made - material, manufacture, making, history, used ... Sand was used as early as 6000 B.C. to grind and polish stones to make ... Quartz sands, which are high in silica content, are used to make glass. ... natural decomposition, extraction, sorting, washing, and in some cases crushing. ... are mobile and can be broken into separate components to be towed to the quarry site.