Mohawkite: Copper, Nickel and Cobalt Arsenide. This mineral is found in the Mohawk Mine, Michigan.
Mica: Any
one of a class of minerals of a foliated structure, consisting of thin
flexible plates or scales, easily separated, and sometimes not more
than a 300,000th part of an inch in
thickness. Some of the varieties are as follows:
Muscovite Phlogopite Lithium Mica
Paragonite Lepidomelane Magnesium-Iron Mica
Lepidolite Potassium Mica Magnesium Mica
Biotite Sodium Mica Iron Mica
Microcline: Potash
Feldspar, of the triclinic system of crystallization. Simple crystals
without twinning are very rare. Color white to cream-yellow, also red
and green, transparent or translucent. Amazonite or Amazonstone is an
apple-green variety of Microcline used for ornamental purposes. At
present the principal use is in the manufacture of porcelain and other
white pottery products and enamel ware; in the manufacture of
opalescent glass, artificial teeth, etc.
Microlite: A mineral related to Pyrochlore, characterized by a
brownish color and resinous luster, and occurring in very
small octahedral crystals. Very rarely it is a beautiful
hyacinth-red. It was first found at Chesterfield, Mass. It also
occurs at Branchville, Conn., and Amelia Court House, Va.
MiUerite: Nickel
Sulphide. Sulphur 35%, Nickel 65%. Occurs in capillary crystals in the
cavities of, and among the crystals of other minerals; also aggregated
into tufts, or woven together like wads of hair. This mineral is
brass-yellow in color, is opaque and elastic. It is an excellent
conductor of electricity. Nowhere does it occur in sufficient
quantities to constitute an ore.
Molybdenite: Sulphide
of Molybdenum. Sulphur 40%, Molybdenum 60%. This mineral is the
sulphide of that rare metal molybdenum, the salts of which are
important chemically, employed principally in analytical work. It
occurs in black scales scattered through rocks and limestones, and in
black or gray foliated masses. Crystals are exceedingly rare.
Molybdenite is found in Norway, Australia, and in Ontario, Maine and
Connecticut.
