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This
affordable gemstone is a popular alternative to sapphire and
tanzanite for those who love deep blue. With its rich colour,
iolite is worthy of attention in its own right. It is also
collectible because of its unusual pleochroism: its color
changes when viewed from different angles. An iolite that is
blue when viewed from above might be almost colourless when
viewed from its side.
History and Lore
The name
iolite comes from the greek ios, which means violet.
When Leif
Ericson and the other legendary Viking explorers ventured
far out into the Atlantic Ocean, they used thin pieces of
iolite to help them find their way. Looking through an
iolite lens, which acted as the world’s first polarizing
filter, they could determine the exact position of the sun,
and navigate safely to the new world and back.
The
property that made iolite so valuable to the Vikings is
extreme pleochroism: the display of different colours in
different directions. A cube cut from iolite may appear
violet blue from one side, colourless from the other and a
honey yellow from the top.
Iolite was
sometimes called “water sapphire” in the past, a misnomer
that is now obsolete.
Quality, Value and availability
Iolite is
readily available and surprisingly affordable. The richer
and brighter the blue, the better. Stones with a grayish
cast to the blue are less expensive.
It is more
common to find iolite with beautiful blue below a carat in
size: larger sizes are often too dark, almost black.
If iolite
is not cut from exactly the right direction, no matter the
shape of the rough, its colour will not show to its best
advantage.The most common shape is oval.
Sources
Iolite is
mined in India, Srilanka, Madagascar, Namibia, Tanzania,
Zimbabwe and Brazil. The Vikings probably mined iolite in
Norway and Greenland.
Routine Enhancements
There are
no routine enhancements for Iolite.
Care and Cleaning
Iolite is
relatively hard, with a hardness of 7 to 7.5 on the Mohs
scale, but should be protected from blows. Clean garnet with
mild dish soap in warm water : use tooth brush to scrub
behind the stone where dust can collect.
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