Amber: An Introduction
Amber, known and valued as a gemstone since at least
Neolithic times, remains popular for jewelry to the
present. Amber is a fossilized resin from various sorts
of trees, mainly a species of pine or a legume. Amber
is a soft, light stone, which as a poor heat conductor
feels warm to the touch. It comes in a variety of colors,
from pale yellow to orange to an almost opaque dark
red, and can be clear, cloudy or opaque depending on
bubbles, inclusions and flow planes, and the surface
can be dull, polished or iridescent depending on polish
and impurities. Most if not all amber is fluorescent
under a black-light. It can be polished easily, because
it is so soft; but it also wears easily for the same
reason.
To scientists, amber is a particular interested because
of inclusions. Amber is well-known for preserving a
variety of small creatures, ranging from micro-organisms
to small lizards and frogs. Most often found are small
flies, midges, gnats and the like but beetles, spiders,
moths and similar creatures are not uncommon. Plant
debris is even more frequently found; one sort of debris
characteristic of Baltic (see
pictures) and related ambers is sort of
"hair" from male oak flowers, not often found
in other varieties. Some of the fossils are of particular
interest; the oldest known ants, for examples, are found
in Cretaceous amber from New Jersey and Lebanon.
Amber is found in many places, and is constantly turning
up on new areas. The two most common types are Baltic,
from the shores of the Baltic Sea, and Dominican, (see
pictures) from mines in northern parts
of the Dominican Republic. Other varieties, less frequently
met with, are from Mexico (Chiapas province), (see
pictures) Burma (Kachin State) (see
pictures), Canada (Alberta), and the USA
(Arkansas, New Jersey). Most other amber-producing sites
are of no commercial importance, as their output is
so small that such amber appears very rarely.
Amber varies widely in age. The newest is semi-fossilized
resins known as "copal", some of which is
barely hardened; the oldest known amber is Carboniferous.
The following table gives a few examples:
|
| Location |
Era |
Age |
Inclusions? |
| Columbia |
Recent |
100-5000 |
y |
| North Carolina |
Miocene |
15,000,000 |
n |
Dominican
Republic |
Oligocene-Miocone |
15,000,000,-40,000,000 |
y |
| Mexico |
Oligocene-Miocone |
22,000,000 - 28,000,000 |
y |
| Baltic Sea |
Eocene-Oligocene |
28,000,000 - 54,000,000 |
y |
| Wyoming |
Palaeocene |
60,000,000 - 65,000,000 |
n |
| Alberta, Canada |
Cretaceous |
70,000,000 - 75,000,000 |
y |
| New Jersey |
Cretaceous |
90,000,000 - 95,000,000 |
y |
| Burma |
Cretaceous |
100,000,000 |
y |
| Lebanon |
Cretaceous |
120,000,000 |
y |
| Bavaria |
Triassic |
250,000,000 |
y |
Many types of imitations have flooded the market since
Roman times. Nowadays they fall into four categories:
plastic, glass, semi-fossil resins ("copals")
and reconstituted amber. Glass is very easy to detect,
as it feels cold, is very hard, and is heavy. Copal
is fairly easy to tell as it feels slightly sticky to
the touch, and is usually much paler than fossil amber.
Plastics can be tricky; some of the books listed below
describe the differences. Reconstituted amber is the
most difficult, sometimes fooling experts; it is after
all, noting more than amber chips made into a large
piece with a "filler" usually melted copal
or something similar. Like any other "collectible"
experience allows the collector to tell quickly what
the novice can only determine "by the book"
Amber nowadays is cheaper than it has ever been, and
information regarding it has never been more available.
We sell examples to fit all interests and budges.
Further reading:
Dahlstrom, A.; Brost, L., Amber book, Tucson, 1996.
General introduction.
Poinar, G. and R.; Amber Forest, Princeton 1999. Dominican
amber inclusions.
Poinar, G.; Life in Amber, book or CD-Rom versions.
General description of inclusions.
Poinar, G. and R.; Search for Life in Amber, Reading,
MA, 1994. General introduction.
Rice, P.C.; Amber, Golden Gem of the Ages, NY 1987.
General introduction.
Ross, A., Amber, Cambridge, MA 1998. Excellent cheap
introduction to inclusions.
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