Gem
World Jewellers
Facts and figures about Amber.
An extremely rare piece of Amber with a Lizard
Amber:
Amber is the hardened resin of
coniferous and angiospermous trees. Resin is not to be
confused with sap which is a product of photosynthesis that
consists of sugars, water and dissolved minerals. The sticky
extrusive mass that comes from a cut on a pine tree is resin.
Under the proper conditions the resin undergoes certain
physical and chemical changes that turn it into amber If the
resin has hardened in recent times, it is called copal.
Presently certain trees produce large quantities of resin; the
Kauri gum from New Zealand (Agathis australis), Sundarac from
Australia (Tetraclinis articulata), the Gum Arabic tree from
Africa (Acacia arabica) and the Algarroba tree from South
America (Hymenaea courbaril). It was trees like these which
produced the resin that often trapped un-suspecting insects
and even larger animals. Like fly paper, the more one
struggled to get free, the more entangled it became.
Each locality produces amber of a distinct type. Often the
location of the amber can be derived visually from the amber
itself. Baltic amber may have a cloudy appearance, due to air
bubbles. The thicker the flow, the more bubbles that remained.
The thinner the flow, the fewer the bubbles. Baltic amber also
has a high percentage of succinic acid, as much as 8% by
weight. In addition this amber often has stellate oak hairs.
Fifteen varieties of trees have been recognized so far from
these hairs . White amber (clear) has been found in Tasmania
and is estimated to be about 2 million years old . Dominican
Republic amber, around 25 million years old, has little
succinic acid in it; the colour is usually clear yellow; is a
bit harder than other amber; and it commonly has ants and
beetles as inclusions . Spectral analysis can reveal the
location and age of most amber.
Pictures of Insects and Spiders in Amber:
Drawing to show the moment an insect is caught in the resin:
Colours Of Amber:
Amber comes in many colours. Typically amber golden yellow, but can also be green, red blue and clear. Surprisingly, it is relatively stab le and is insoluble even in many organic solvents. It has a specific gravity of 1.05 to 1.09 and therefore floats - it should sink if the specific gravity is greater than 1. The Greeks believed that amber was the petrification of sunrays; some even felt that it was petrified tears. They prized amber for the magical properties that electricity exhibited when rubbed. The term electricity is derived from the Greek word, elektron, which is also the Greek word for amber . In modern times different uses for the "petrified sunlight" have been found. In the 1800's amber was melted and used as a finish on sailboats and other marine ships. Larger pieces of amber have been used by artists for sculpturing. Some has been melted down and re-solidified into ambroid for costume jewellery. The better quality amber was and often is polished and used for jewellery.
Pictures of Insects and spiders in Amber:
Prehistoric:
The selective entrapping of insects and other small animals is a fascinating aspect of the fossil. Large animals are often strong enough to break free of the sticky resin, while small insects such as ants, bees, beetles and mites are usually not strong enough to break free from its hold. It is for this reason that animals most often-found in amber are Arthropods. In New Jersey the oldest ants (workers) have been found, dating from the Cretaceous period, confirming that sociality has existed as far back as 100 million years ago. It is with these small animals that many questions for modern scientists are revealed.
Bacteria that existed millions of
years ago are probably still in and on the trapped animals.
Could they still be alive? Might they carry disease organisms
that have long since become extinct? Could they carry resistant plasmids that scientists may be able to use? In March of
1982 in Science magazine, Roberta Hess and George Poinar, Jr.
announced that the discovery of cellular components in
embedded insects. They found such cellular detail as nuclei,
ribosomes and chromosomes. Their efforts to try and sequence
the possible DNA failed. However, since then many advances in
DNA cloning have occurred. In particular the polymerase chain
reaction (PCR) which allows millions of copies of DNA to be
made from a very small original sample in a short time. Now,
even DNA from fingerprints can be analyzed. Could we clone an
ant with the small amount of material left? What about mites
and other parasitic creatures that infected dinosaurs and
other prehistoric animals? Might they have blood and skin from
their hosts? Would it be possible to clone a dinosaur from a
few cells in the gut of a mite?
One unique thing about inclusions in amber is that the animals
are not fossils in the classic sense. Most fossils are the
imprint or bony remains of an organism. Amber has the actual
animal itself ! While usually all that remains is a
carbonaceous crust, sometimes soft parts do survive . Recently
even the air bubbles that reside in different ambers have been
analyzed to determined the composition of an atmosphere at
that time. It is with these that the future dreams of research
reside.
When students view the sample, the same excitement that I have always felt surges through them. My students are always interested in the "real-life" aspect of the fossilized insects. Showing the amber sample and relating it to the geologic time line, or life as it was in the prehistoric time is particularly effective. With an over head projector, a dissecting microscope or just hand held observation, students experience awe in seeing the real creature. Students can readily acquire their own samples as amber, with inclusion such as insects and other organic debris, is available at rock and mineral shops from $5 to $40 a sample. It is with amber that one can easily see into past life. It combines beauty and history. It is truly a golden eyepiece to the past.
Thanks to Doug Lundberg for material on this page.
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