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Amber 2
Next, two common organic liquids are used: benzole,
which dissolves polystyrene fairl, rapidly, making it go soft
and stringy, and ethyl alcohc (ordinary denatured alcohol),
which softens the surface c, copal in less than half a minute,
so that if the specimen is rubbed against a piece of white
cloth, it leaves a distincmark, the friction also producing
visible signs of abrasion In this way, amber can be quite
rapidly and positively identified, because it is not attacked
by either benzole or alcohol. Partial immersion in alcohol
also helps make another distinction: pieces are often found
which have the basic characteristics of amber, but in fact
consist of an agglomeration of numerous small fragments of
amber (offcuts or pieces that were too small to begin with)
that have been heated and compressed. In this case, a type
of mosaic is visible with a lens on polished surfaces, because
the contiguous pieces have slightly different hardnesses and
show different relief when polished. Immersion in alcohol
for between half a minute and two minutes causes the parts
that have been softened by heat to turn slightly opaque, still
further emphasizing the mosaic effect. Amber's famous ability
to develop an electric charge and pick up pieces of paper
if rubbed is not a useful means of distinction, as copal and
nearly all plastics have the same property.
Occurrence In the past, most amber came from
the southern coastal areas of the Baltic, which are now part
of Poland and the Soviet Union. Other areas, such as Romania
and Sicily, were much less important: Amber usable for Carving
in amber. ornamental purposes has also been found in Burmahome
of many of the principal gemstones-and larc quantities of
very fine amber have also been obtained f more than a decade
from the Dominican Republic.
Value Nowadays it is quite low, or at any
rate, mu; lower than it must have been many centuries ago.
obviously, antique and/or finely worked pieces are an exception
to this rule, but they are not often seen.
Simulants Ever since production
of plastics began se. eral decades ago, they have nearly all
been used to imitav amber. Large amounts of old-fashioned
jewelry, therefor are in circulation which are believed to
be amber but are. fact, plastic. In the Orient (mainly India
and China) various sculpted or engraved objects have been
produced, son of them quite large, which are now coming onto
the mark, as old or antique, but which are made of plastic
fashione like amber. Many modern pieces of silver jewelry
of Arab or African origin are now set with pieces of plastic
instea: of amber. Copal is sometimes used for these as well.
A though less valuable because it is unstable and liable to
d, teriorate, it is at least a natural material. The tremendous
confusion on the market and the difficulty of distinguishin
amber readily from many types of plastic, not to mentic agglomerated
amber and copal, have greatly diminishethe respect this material
enjoyed in the past.
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