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Ch. 64: Amber

Ch. 63: Alabaster (Calcite, Gypsum) Page of 252 Ch. 64: Amber Text size:minus plus Restore normal size   Mail page  Print this page
AMBER
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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Ch. 63: Alabaster (Calcite, Gypsum) Page of 252 Ch. 64: Amber
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