hard rock Definition

asa, granite, cafe, beryl, diamond, flint, quartz, agate, silex, marble, quartzite, rocky, stone, tabby, basalt, metal, ore, porphyry, tufa, chert, novaculite, whinstone, tuff, alternative, blanch, blanched, buhrstone, cliff, clint, feldspar, flagstone, greywacke, heavy, hook, hooking, hooks, hornfels, jackhammer, jook, lava, metals, mole, petrogenesis, rocks, shale, stoned, stoning, stony, burr, cap, consolidation, irestone, lordi, peridotite, raging, slade, stale, tesla, ironstone, rimrock, monadnock, platy, roach, rock cake, shorter, vermiculite, adamant, against, aggregate, aggregated, almond, beat, blast, coal, concretion, core, coring, crack, cream, crystal, drill, elm, grain, greenstone, grit, grits, groove, habit, hammer, hammered, hammering, hammers, heave, horae, horse, industrial, ironbound, jack, jacked, jacking,