QUARTZ CONTAINS SILICA. WHEN CUTTING, GRINDING OR DRILLING THIS PRODUCT, DANGEROUS CRYSTALLINE SILICA (SiO2) DUST IS RELEASE INTO THE AIR. LONG TERM UNPROTECTED EXPOSURE TO THIS DUST MAY CAUSE SERIOUS DISEASES AS PNEUMOCONIOSIS, BRONCHITIS, ENPHYSEMA, ETC. MORE INFORMATION AND GOVERNMENTAL REGULATIONS CAN BE FOUND AT OSHA.GOV/SILICA-CRYSTALLINE