Gold: This
element is among the most valuable of metals, ranking second only to
Platinum. It is of a bright yellow color and the most ductile of all
the metals. It can be beaten into leaves so thin that one grain in
weight, will cover 56 square inches. It occurs crystallized, in plates,
massive, in flattened grains or scales, and in rolled masses in sand or
gravel. These rolled masses, when of some size, are called nuggets; in
rare cases these occur very large and are of great value. The
Australian Gold region has yielded many large nuggets, one found in
1858, weighing 184 pounds, and another in 1869, weighing 190 pounds. (Dana pg. 16.)
Gold
constitutes the principal medium for coinage in nearly all of the most
important countries of the world. The gold coins in the United States
contain 900 parts gold in 1,000.
Its
uses for jewelry are well known, it being particularly well fitted for
this use on account of its imperviousness to tarnish. Pure gold is
golden-yellow, but with increase of silver it becomes lighter, and with
increase of copper, darker. California gold is 88% fine on an average,
though many analyses run up to 95 % and even higher.
Gold
is found in Siberia, the Ural Mountains, Brazil, Central and South
America, Australia, Alaska, California, Colorado, Montana, Nevada, and
many other places.
Gold amalgam is a variety containing 57.4% mercury.
Graphite: Carbon,
often impure from the presence of iron and clay. It occurs in six-sided
crystals, foliated masses, columnar or radiated, scaly or slaty,
granular or earthy, iron-black to dark steel-gray in color. A conductor
of electricity. This form of carbon, being soft and black is adaptable
to the manufacture of lead-pencils, which are really graphite Qpencils.
Graphite is important as a lubricant for heavy machinery. It is used
in the manufacture of stove and other polishes, of black paint for
metal surfaces, for both of which it is valuable on account of its
non-corroding properties.
Greenockite: Cadmium
Sulphide. A source of cadmium of which it contains 78%. This mineral
usually occurs as a coating on other minerals, especially Sphalerite
and is honey to orange-yellow in color. It is named after Lord
Greenock, its discoverer and occurs in Scotland, Bohemia, and at
Laurium, Greece. In the United States, in Lehigh Co., Pa., in Missouri, and Arkansas.
Grossularite Sometimes called "Cinnamon Stone" or "Cinnamon Essonite: Garnet." A variety of Garnet usually of a cinna-
mon
brown color, or some pale shade of red or green. Much of the "Hyacinth"
of the jewelers is a red Grossularite. This variety of garnet is used
as a gem stone.
