SOURCE OF SPINEL
The current main sources of
spinel are Myanmar, Sri Lanka,
and Tanzania. Mining also
takes place in Afghanistan,
Thailand, and Russia. Most
spinels are mined from alluvial
deposits, where rough crystals
that were transported by
ancient rivers accumulated
along with dirt and gravel. |
 |
Weight : 0.73
ct
Size (mm): L 7.4 x W 4.8 x
D 2.79
untreated
US $400 |
Tanzania
The Tunduru mines, located
approximately 400 kilometers
(240 miles) south of Dar-es-Salaam,
have been operating since
late 1994. Tundurn is an
area of alluvial deposits
spanning 40 kilometers (24
miles), said to be worked
by some 4,000 miners. Red
spinel is mined here, along
with diamond, sapphire, alexandrite,
cat's eye chrysoberyl, tsavorite,
and tourmaline. Most of the
spinel is accessory-quality
material falling within tone
levels 2 and 1 and beauty
grades A through D on the
quality scale. However, some
bright pink material like
the one shown in the photograph
is also mined. |
|
|
Sri Lanka
Blue, violet, and black spinels are
mined in the Ratnapura area of
southwest Sri Lanka, but red spinel
production is rare. The surfaces
of the rough gemstones found here
are weathered and worn.
|
Weight : 1.07 ct
Size (mm): L 7.1 x W 5.2 x D
3.70
untreated
US $200 |
 |
 |
Weight : 0.88 ct
Size (mm): L 7.0 x W 5.1 x D
3.17
untreated
US $100 |
Myanmar
The Mogok region of Myanmar is famous
for its rubies and sapphires, but
it is also a source of orange,
green, blue, and violet spinels.
In addition, limited qualities
of fine-quality red and pink spinels
are mined here. Rough crystals
with weatherworn surfaces are found
here also, as well as perfectly
formed octahedral crystals. |
|
 |
JUDGING QUALITY
When judging the quality of red spinel,
the darker colors seen in stones
from Mogok and lighter colors of
Tanzanian material are considered
separately. Darker spinels typically
resemble rubies, but when compared
side-by side, the difference between
the purplish red of ruby and the
crimson red of spinel becomes obvious.
Spinels will look slightly orange
to the eye that is accustomed to
the purple-red of rubies.
Red spinel that exhibits the beauty
of a crimson-red mosaic pattern is
considered gem quality. Some lighter
red spinels are highly transparent,
giving them a clear and pleasing
quality. These are classified as
jewelry quality because of their
light tone, but some of them possess
a beauty that surpasses gem quality
and deserve very much to be used
in jewelry. |
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