noted
for these Meteorites, and many have been seen to fall. Some of the
masses are very large, one in Mexico having been estimated to weight 5
tons. One found in Texas, weighed 1,635 pounds. On the other hand some
have been so small that they resemble shot, (see Hematite).
Jade: Any
of various ornamental green stones, especially a Silicate of Sodium.
Included in the massive varieties are two mineral species, namely
Pyroxene and Amphibole. It is found in a wide range of colors from pure
white to various shades of green, yellow, pink, bluish and even black.
It is much prized in the far East, especially by the Chinese, who call
it Yu or Yu-shih. They have used it for ages as a carving material and
their unique designs and beautiful workmanship result in unusually
handsome pieces. Jade lends itself to the most intricate and decorative
carving and from prehistoric times has furnished primitive man with a
hard, tough, compact material out of which he has fashioned weapons,
ornaments and other expressions of his culture.
The
name is from the Spanish "Piedra de Yjada," meaning "stone of the
side," so-called because the wearing of the stone was supposed to cure
pains in the side.
In the United States, Jade is very popular and much used in ornamental jewelry.
Jadeite: Silicate of Sodium and Aluminium. It occurs massive, with crystalline structure, and sometimes granular; is extremely
tough; color emerald-green to apple-green, bluish-green, leek-green,
greenish-white and nearly white. Translucent to subtranslucent.
Jadeite has for ages been used extensively by the Chinese, who carve it
into ornaments and utensils of great variety and beauty.
It occurs chiefly in Eastern Asia.
Jamesonite: Sulphur 20%, Antimony 30%, Lead 50%. Some
varieties show a little iron, and some a little silver,
copper and zinc. Occurs usually in acicular crystals;
in capillary forms, cobweb-like, also massive. Color steel-gray to
lead-gray. Occurs principally in Cornwall, England.
Jasper:
A variety of Quartz that is impure and opaque, and colored red, brown,
yellow, green or some dull shade. When the colors are in stripes or
bands, it is called "banded or striped
Jasper." It is used for ornamental purposes.
Among the varieties, is Basonite or Touchstone, used by jewelers
and goldsmiths as a test for the purity of gold and its alloys. This
variety is a velvety black jasper.
