Economic Geology: Or, Geology in Its Relations to the Arts and Manufactures

abundance admixture agricultural alumina amount antimony arsenic arts and manufactures basalts beds bismuth bituminous blocks Britain calcareous carbonate carbonic acid Carboniferous cements chalk chemical chiefly chloride clay clayey coal colour compact composition consists containing copper crust crystalline crystals deposits districts durable earth employed engineer felspar fire-clays formations geologist Geology gold granites gravels Greensand greenstones grits gypsum hard heat hence hornblende igneous ingredients iron ironstones known largely lignites lime limestones lustre magnesia manganese manures marbles marls masses material metamorphic mineral and metallic mortar nature obtained occasionally occur Oolite ornamental oxide peat phosphate pigments polish porphyries potash preparation purposes pyrites quarries quartz require rocks saline salts sand sandstones schists serpentines shales silica Silurian silver soda sodium soft soils specific gravity stones strata stratified structure subsoils substances sulphate sulphide sulphuric acid surface tellurium tertiary texture thickness tion tons usually varieties various vary veins volcanic yield zinc