Dark
Green Spinel called Ceylonite is
a Rare color of spinel found only
in Sri Lanka.
Spinel
is commonly found in alluvial gravels
with corundum and also in association
with with gneiss, serpentine, calcite,
dolomite, and garnet.
With
a hardness of 8 and no cleavage
planes, spinel is a tough and durable
gemstone suitable for any kind of
jewelry. Its’ luster is vitreous
and rough crystals can be transparent,
translucent or nearly opaque. A
member of the isometric system,
the octahedron is the typical habit.
Dodecahedrons and combinations of
other isometric forms are also common.
Many crystals are twinned on the
plane of the octahedral face forming
flattened triangular forms known
as “spinel twins”.
Precious
spinels appear strikingly clean
and free of inclusions. This impression
is due among other things to the
lack of liquid inclusions. The best
proof of spinel is spinel and microscopic
octahedra may be scattered in long
chains and sinuous bands throughout
inner stretches of the host crystal.
Besides these mini spinels, spinel
shelters a whole range of other
guest minerals including albite,
anhydrite, apatite, baddeleyite,
calcite, olivine, and titanite.
History
-
1)
Perhaps the most famous spinel is
the "Black Prince's Ruby",
a magnificent 170-carat red spinel
that currently adorns the Imperial
State Crown in the British Crown
Jewels. This stone as large as a
hen's egg, weighing approximately
170 carats. Spectacular red that
seems to glow with an internal fire
of its own. It's actually a spinel
with a long and fascinating history.
2)
The Timur Ruby, also in the Crown
Jewels of England, is even larger,
weighing 361 carats. It is inscribed
with the names of six of its former
owners. This is also a Spinel.
3)
The Kremlin Museum in Moscow has
another giant gem that probably
belonged to the Tsar - weighs 414
carats.
4)
The most dazzling collection of
fine red spinels is found in the
Crown Jewels of Iran. The majority
were plundered from India when the
Mogul Empire fell. The largest one
weighs about 500 carats, and it
is indeed the biggest on record.
Many others weigh over 100 carats,
and more than a dozen have been
carved with the name of Jahangir,
a Mogul emperor over 350 years ago.
Red
spinel has never been as abundant
as ruby, and today it is quite difficult
to find. The old mines in Afghanistan
have been worked out, and the gem
gravels of Sri Lanka and Africa,
which provide us with many beautiful
pastel colored spinels, rarely contain
gems with the pure intense red color.
