+-----------------+-------------------------+--------------------------+ |=Name of Mineral=| =Varieties= | =Remarks= | +-----------------+-------------------------+--------------------------+ |=Amphibole.= |Actinolite (green, trans-|Common constituent of | | |parent). Asbestos |igneous and metamorphic | | |(fibrous, dull). Horn- |rocks. Valueless. | | |blende (black). | | | | | | |=Arsenopyrite.= |... |Principal ore of arsenic | | | |and sometimes carries | | | |gold. Gives sparks and | | | |garlic odor when struck | | | |with a hammer. Yellow | | | |tarnish. | | | | | |=Barite.= |... |Used to adulterate white | | | |lead and give weight to | | | |paper. Often associated | | | |with lead ores. Very | | | |heavy. | | | | | |=Biotite.= |... |Common constituent of | | | |igneous rocks. May be | | | |brittle when altered. | | | |Valueless. | | | | | |=Calcite.= |Marble (granular). Lime- |Effervesces vigorously in | | |stone (dull, compact). |hydrochloric acid of any | | |Chalk (soft, white, |strength and temperature. | | |earthy). Mexican Onyx |Used as flux, building or | | |(compact, banded). |ornamental stone, to make | | | |lime, etc. | | | | | |=Chalcocite.= |... |An important ore of | | | |copper. Cuts easily, | | | |yielding a highly polished| | | |surface. | | | | | |=Chalcopyrite.= |... |One of the most important | | | |ores of copper and often | | | |carries silver and gold. | | | |Is often mistaken for the | | | |latter. | | | | | |=Copper.= |... |The value and uses of | | | |copper are well known. | | | |Often carries some silver.| | | | | |=Corundum.= |Ruby (red). Sapphire |A very valuable gem | | |(blue, etc.). Adamantine.|mineral and a fine | | |Spar (massive). Emery |abrasive. See plate I, | | |(granular, impure). |figures 10, 11 and 13. | | | | | |=Epidote.= |... |Common constituent of | | | |metamorphic rocks. Rarely | | | |cut as a gem. | | | | | |=Fluorite.= |Rock fluorite (finely |Used as a flux in smelting| | |granular and usually very|ores, and in several arts | | |impure and hard). |and trades. | | | | | |=Galenite.= |Steel galena (very fine |Most important lead and | | |grained masses). Often |silver ore. Often contains| | |rich in silver. |the latter metal with | | | |sometimes gold and other | | | |elements. | | | | | |=Garnet.= |... |An important abrasive and | | | |a beautiful gem. Found in | | | |metamorphic rocks. See | | | |plate I, figures 8 and 15.| | | | | |=Gold.= |Based upon and named |The value and uses of gold| | |after any impurities that|are well known. | | |may be present. | | | | | | |=Graphite.= |... |Used in the manufacture of| | | |lubricants, infusible | | | |crucibles, and “lead” | | | |pencils. | | | | | |=Gypsum.= |Selenite (cleavable, |Is carved into vases, | | |transparent). Satin spar |statues, etc., and forms | | |(white, fibrous, silky). |plaster of paris when | | |Alabaster, (white, fine |calcined and ground. Is a | | |grained). |precipitate rock. | | | | | |=Halite.= |... |Tastes salty. Enormous | | | |quantities are used to | | | |season food, in various | | | |arts and trades, and as a | | | |source of sodium and its | | | |salts. A precipitate rock.| | | | | |=Hematite.= |Specular iron (mirror- |The most important ore of | | |like plates or crystals).|iron, and is also used to | | |Red Ochre or Ruddle (red,|make cheap paint, | | |earthy). |polishing powder, etc. | | | | | |=Limonite.= |Bog iron ore (porous, |Commonest, but most impure| | |earthy, often encloses |ore of iron, and is also | | |vegetation). Yellow ochre|used to make cheap yellow | | |or umber (earthy with |and brown paint. | | |clay, etc.). | | | | | | |=Magnetite.= |Lodestone (a natural |The only black, brittle, | | |magnet). |magnetic mineral, and a | | | |very pure and valuable | | | |ore of iron. | | | | | |=Malachite.= |... |Is an ore of copper and is| | | |used as an ornamental | | | |stone and in jewelry. | | | |Azur-malachite is | | | |malachite mixed with blue | | | |azurite. See plate I, | | | |figure 4. | | | | | |=Muscovite.= |... |Used in stove doors, as | | | |insulation in electrical | | | |apparatus, and for | | | |spangling or frosting | | | |paper and fabric. | | | | | |=Orthoclase.= |Sanadine (transparent |Associated with quartz and| | |crystals or grains im- |mica in many rocks. Used | | |bedded in igneous rocks).|in making glass and | | | |porcelain. Next to quartz | | | |in frequency of | | | |occurrence. | | | | | |=Pyrite.= |... |Used in making sulphuric | | | |acid and often contains so| | | |much gold, silver and | | | |copper as to make it an | | | |ore of these metals. | | | | | |=Pyrolusite.= |... |Has many uses and is | | | |valuable. Usually | | | |associated with a very | | | |fine grained, hard, black | | | |mineral that is often | | | |botryoidal.