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by vanadium, color is very stable to any light change and heat, changes are only
above around 700-800 ° C.
The color distribution is often
in patches of darker and lighter zones, inclusions are
rather normal, the higher the transparency the better the
quality, its somehow similar to jade. It needs to be very
careful when there are no inclusions, that “smells fishy”.
The physical data, especially the density, and light
refraction are a bit different depending from which deposit
the stone comes. The Emerald gemstone has a brittleness which makes it
pressure sensitive when heated.
The emerald mines during Cleopatra’s times
have only historical significance
today. Once the global source of supply has been Egypt, for
about 1500 years (starting around 300BC) the “mines of
Cleopatra”, about 500 kilometers south of Cairo, were the
significant source of the green crystals, the old Egyptians
and after Romans and Turks extracted the precious stones
from the desert. At those times people gave various
attributes to the green stones including magical and health.
Since all kind of superstition were projected into the
minerals including something into the sex direction busy
trade was going on even all the remote areas in south Asia.
The Egyptian had a comfortable
monopoly on Emeralds until about the 16th Century when the
Spaniards conquered “Incaland” and in 1558 they discovered
the mines at Muzo not far from Bogota, this mines are even
today a major source for exquisite emeralds. Quickly
production was expanded and a stream beautiful emeralds
reached Europe, the story is somehow similar to the Spanish
madness for gold.
All rulers of Europe plus Turks,
Persian Shahs and Indian Maharajas became customers of the
Spaniards since now they had some kind of monopole for the
green crystals because the mines of Egypt were exhausted
long time ago. There are several collections of
the green stones among the most interesting are the
Persian
crown treasure. In
recent decades with new exploration techniques, more
promising emerald deposits in Colombia have been found.
Always in high demand are the very rare Trapiche-emeralds,
occurring only in Colombia they get their particular
appearance by a special form of crystals.
In Brazil are also many deposits
with a bit brighter stones than
of Columbia, having a bit of a yellow green shade but they
are often free from inclusions.
In about 1830 Russian emerald deposits
north of Yekaterinburg in the
Urals were discovered but quality is poor just
as it is with everything which comes from Russia.
Since the second half of the 195X ties deposits in Zimbabwe
are being exploited. Best known
is the Sandawana mine in the south of the country, crystals
are rather small, but quality is excellent.
In the Northern Transvaal (South Africa) the stones
are mined at the (Cobra and
Somerset mine) but only around 7% of production is of good
quality. Most stones are only suitable for cabochon.
More deposits are in
Afghanistan, Australia, Chile, China, India, Madagascar,
Mozambique, Namibia, Pakistan, Zambia, Tanzania and USA.
Emeralds are created in interaction of moving magma and
metamorphic rock transformation.
The most important deposits are
located in Colombia. Important sites are the Muzo mines,
north-west of Bogotá. Already exploited by the Incas, then
forgotten and rediscovered in the 17th Century. This often
delivers the best qualities of the right deep green color.
Mining takes place by tunneling and step terraces. By
blasting or bulldozing the earth and soft rock is loosened
and then sorted by hand. Another major emerald
gemstone
deposit is the mine of Chivor, northeast of Bogotá, also
already used by the Incas.
A certain
Emerald jewelry cut has been created
over time called “emerald cut”
this cut takes the physical
properties of the crystals under consideration to avoid
breaking. Emerald jewelry was always the interest around the
green crystals, although some health and curing properties
have been interpreted into the green stones the main
attraction always was the crystal itself, the bigger and
clearer the better. Celebrities have their share in a recent
upsurge in demand for great green stones its somehow similar
to pink diamonds, after those were spotted somewhere hanging
on a celebrity all women with money started a stampede which
was the best what could have happen to the Argyle Mine in
Australia which has almost a monopoly for good pink
diamonds.
These beautiful green minerals
are a sure eye-catcher on every woman’s body, although it
needs a certain size to really notice them, but there are
some tricks to help with this. Since a emerald itself wont
sparkle and draw attention some diamonds are placed around
and the visibility grow exponentially this is somehow
similar to jade since properties are also a bit similar. |
