|
Ludwigite: Possible
composition: Boron Trioxide 16%, Iron Ses-quioxide 38%, Iron Protoxide
17%. It occurs in finely fibrous masses with fibers often radiating;
also short and interwoven, tough but easily cut. Color blackish-green
to nearly black with a tinge of violet; greenish-brown in small
splinters and strongly pleochroic. It is found in Hungary and is named
after Ernest Ludwig, Professor of Chemistry at Vienna.
Magnesia:
A primitive earth composed of Magnesium Oxide. A soft white powder
without taste or smell, that is anti-acid and mildly cathartic.
Magnesite: Carbonate
of Magnesium. Carbon Dioxide 52%, Magnesia 48%. This mineral occurs in
fine-grained white masses; crystals are rare. It is employed largely in
the manufacture of bricks used for lining converters in steel works,
and in the lining of kilns. It is also used in the manufacture of paper
from wood-pulp and in making artificial marble tile. From it are also
made Epsom salts, magnesia and the carbon dioxide used in making soda
water. All the Magnesite mined in the United States comes from
California.
Magnetite: Ferrous
Iron Oxide, containing 72.4% Iron. It occurs in crystals, in granular
structureless masses, and as loose sand; is black and opaque. It is
magnetic, and the variety known as lodestode, is highly magnetic,
pointing to the Poles when freely suspended. The name is derived from
Magnes, who first discovered it, so the story runs, by finding on
taking his herds to pasture, that the nails of his shoes and the iron
ferrule of his staff, adhered to the ground.
It
is thought that the unknown people of the south-west, percur-sors of
the American Indian, must have used this natural magnet to orient their
temples, as they are all placed parallel to the magnetic meridian.
The
localities of its occurrence are very numerous. The most important
native magnets are found in Siberia, Harz, the Isle of Elba, and at
Magnet Cove, Arkansas.
Magnetite ranks next to Hematite in importance for the production of iron.
Malachite: Green Carbonate of Copper. Carbon Dioxide 20%,
Cupric Oxide 72%, Water 8%. Occurs in small
drusy crystals, commonly massive or incrusting; often
delicately compact, fibrous and banded in color; frequently granular
or earthy. A velvety massive form is called Velvet Malachite. Color
|
||
|
|
||
|
Forty-one
|
||
|
|
||