the
Chinese Empire; and wherever on the globe adventurous Chinese roam or
locate it is always found as one of their most cherished possessions.
Properly the term " jade " includes but two minerals; nephrite and
jadeite. Nephrite is Nephrus amorphous of the order Chalicinea,
according to Dana's system of mineralogy. The name is from a Greek word
meaning a kidney; the ancient Greeks believing this mineral to possess
the virtue of a specific remedy for all diseases of the kidneys, as,
indeed, the Chinese believe now, and have for centuries. Jade is
massive, of fine granular or impalpable substance; hardness, 6.5;
specific gravity, 2.96 to 3.1; lustre, vitreous; streak, white; colour,
leek-green, passing into blue, grey, and white; translucent to
sub-translucent; fracture, coarse and splintery. An average specimen
contains silica, 50; magnesia, 31; alumina, 10; oxide of iron, 5.5; and
nearly three per cent, of water, with a tinge of chrome oxide. Jade is
infusible before the blowpipe, but becomes white; with borax it forms
clear glass.
Jadeite
is a tough, fibrous foliated, to closely compact, mineral, grouped with
the pyroxenes; hardness, 6.5 to 7; specific gravity, 3.33 to 3.35.
Jadeite will fuse readily before the blowpipe to
