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Collectable's Corner Information
Chrysoberyl
(alexandrite, Cat’s Eye...)
Alexandrite and cat’s eye – look very different, yet they are
the same mineral – chrysoberyl. A less expensive type of chrysoberyl
is transparent, shows no optical effects and ranges in colour from
green, to yellow to brown. Thanks to their good hardness and
durability, chrysoberyls are well suited for jewellery use. Today,
Brazil and Sri Lanka are the most important sources of chrysoberyls. Deposits are also found in Russia, Tanzania, Zimbabwe, Madagascar
and Myanmar (Burma)....
Alexandrite
This gem was first discovered in the Ural mountains of Russia
in 1830 on the 12th birthday of Czar Alexander II, hence
the name. In its finest qualities, Alexandrite looks green in
sunlight and purplish-red under incandescent light (light bulbs).
Coincidentally, red and green were the colours of the Russian
Imperial Guard. Don’t expect to find natural alexandrite in your
local jewellery store --- it’s very rare. When you do see if for sale,
the colours are likely to be a grayish green and brownish purple or
lavender. Synthetic alexandrite and synthetic alexandrite – like
sapphire or spinel are readily available. Prices for natural
alexandrites above a carat that show a noticeable change of colour
start at about $1500 per carat retail and can go over $20,000 per
carat depending on size and quality. The distinctness of the colour
change and the colour intensity are the most important price factors,
but size and clarity also affect the cost.
Cat’s – Eye
Treasured for centuries in the Orient, cat’s eye became
popular in Europe in the late 19th century when the Duke
of Connaught gave a cat’s-eye engagement ring to Princess Louise
Margaret of Prussia. Today, cat’s-eye is used mostly in men’s
jewellery. Other minerals such as quartz, tourmaline and beryl may
also display a cat’s-eye (stripe of reflected light across a
cabochon), but chrysoberyl cat’s eye is the most prized and has the
sharpest eye. The unmodified term cats eyes means chrysoberyl
cat’s eye. Other cat’s-eye stones must indicate the mineral, as for
example, cat’s-eye quartz or quartz cat’s-eye. A brownish yellow
similar to the colour of honey is the most valued colour, but
greenish-yellow stones can also be very expensive. In the finest
qualities, cat’s-eye can wholesale for over $3,000 per carat. Stones
with fuzzy, non-sharp eyes, dull colours and eye-visible inclusions
can sell for less than $100 per carat. Cat’s-eye can also display a
colour change. Alexandrite cat’s eye, however, are quite rare.
Yellow, Green or
Brown (transparent) Chrysoberyl
Attractive and durable, high –quality yellow or green
chrysoberyl is affordably is affordably priced between $100 and $500
per carat, depending on size. Unfortunately, you won’t find it in
many jewellery stores.
Sphene
Sphene is usually yellow, green,
orange or brown and is noted for its diamond-like luster and
exceptional fire (dispersion). Brazil and Madagascar are the
main sources (Newman, 2003).
Collectable gemstones can be securely purchased on this
web site at bargain prices ... see
here
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