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AMBER
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Few
minerals have been longer in favor for ornamental purposes than amber.
Among remains of the earliest peoples, such as the Egyptians and
cave-dwellers of Switzerland, it is found in carved masses, indicating
that it was highly prized. The Phoenicians are said to have sailed to
the Baltic for the purpose of procuring it, while the Greeks' knowledge
of it is indelibly preserved in our word electricity, derived from
their word elektron.
Amber is a fossil gum of trees of the genus Pinus, and
is thus a vegetable rather than mineral product. In color it is yellow,
varying to reddish, brownish, and whitish. Its hardness is 2 to 2.5, it
being slightly harder than gypsum and softer than calcite. It cannot be
scratched by the finger nail, but easily and deeply with a knife. It is
also brittle. Its specific gravity is scarcely greater than that of
water, the exact specific weight being 1.05-1.096. It thus almost
floats in water, especially sea water. It is transparent to
translucent. On being heated it becomes soft at 150° C, and at 250° to
300° melts. It also burns readily and at a low temperature, a fact
which has given rise to the name of bernstein, by which the Germans know it, and to' one of the Roman names for it, lapis ardens. Rubbed
with a cloth it becomes strongly electric, attracting bits of paper,
etc. As already noted, our word electricity comes from the Greek for
amber, this seeming to be one of the first minerals in which this
property was noted. Amber, being a poor conductor of heat, feels warm
rather than cold in the hand, contrary to most minerals. It is attacked
but slowly by alcohol, ether, and similar solvents, a property by which
it may be distinguished from most modern gums and some other fossil
ones. In composition it is an oxygenated hydrocarbon, the percentages
of these elements being in an average sample: carbon, 78.94, hydrogen,
10.53, and oxygen, 10.53. The mineralogical name of amber is succinite,
a word derived from the Latin succum, juice. One of its constituents is the organic acid called succinic acid.
The
present source of most of the amber of commerce is the Prussian coast
of the Baltic Sea, between Memel and Dantzig, although it is found as
far west as Schleswig-Holstein and the Frisian Islands, and
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