The mining and quarrying of such materials as gypsum; asbestos; mica; quartz; natural abrasives other than sand, graphite, talc and soapstone; natural gem stones; asphalt and bitumen; peat; and all other non-metallic minerals not elsewhere classified. The Milling, grinding, pulverizing and otherwise treating these minerals when not performed in conjunction with the extraction or quarrying, is classified in group 3699 (manufacture of non-metallic mineral products n.e.c.).