Amber
is non-crystalline, translucent, and somewhat brittle ; it has a
specific gravity as nearly as possible the same as that of sea-water.
Its fundamental colour is yellow in all shades, running on one side
into white and hyacinth red, and on the other into brown and black. The
green and blue specimens are never pure.
It
becomes electrical by friction, and this property was familiar to the
Greeks as far back as the days of Thaïes of Miletus, who observed that
when rubbed it acquired the property of attracting light substances.
The word Electricity is, in fact, derived from the Greek word electron^ signifying Amber.
Chemically, Amber is composed of a volatile oil, several resins, and succinic acid. The principal resin of Amber is known as Succinite—a name often applied by mineralogists to Amber itself. The Sicilian Amber, of rather different composition, is termed Simetite, after the River Simeto where it is found.
Wherever
Amber is found, whether in France, Holland, Sweden, Italy, Sicily,
Spain, Siberia, China or India, it is in association with brown-coal or
lignite. The most prolific fields of Amber are the great plains of
northern Germany, and the coasts of the Baltic, especially between
Königsberg and Memel, where it occurs in a loose clayey sandstone,
which, from its colour, is known as "blue earth." At Palmicken, in
Samland, in eastern Prussia, the Amber is systematically worked by
subterranean mining ; but in most places the Amber gatherers simply dig
it from the soil, or pick it from the cliffs, or collect the nodules
that are cast by the waves upon the shore.
Specimens
of Amber, in the form of rolled nodules, are occasionally found washed
ashore in this country, especially on the coast of Norfolk, near
Cromer.____