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Click on a
letter above to view the list of gems. |
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| Chemistry:
(Mg,Fe,Mn)2SiO4 | Discovered
in 1996;
IMA
status: Not Valid (tradename) Dunilite
is named after its discoverer, Dunil Paligha Gunasekara
(1947 - ),
F.G.A., a gemologist from Sri Lanka. |
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Classification
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Mineral
Classification: |
Silicates |
Strunz 8th
Ed. ID:
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8/A.04-X |
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8 : Silicates A : Nesosilicates, with [SiO4]4- groups,
cations of tetrahedric orientation [4] 04 : Olivine group
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Crystal
Data
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Crystallography:
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Orthorhombic
- Dipyramidal |
Crystal
Habit:
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Crystals
are tabular, flattened, rectangle shape corners often
modified by a six-sided rhomb shape crystal faces.
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Physical
Properties
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Cleavage: |
[001] Good, [010] Distinct
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Fracture: |
Conchoidal
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Tenacity:
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Brittle
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Moh's
Hardness: |
6.5 |
Density:
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3.48 (g/cm3) |
Radioactivity:
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Not
Radioactive
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Optical
Properties
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Color: |
Greenish
Yellow |
Transparency: |
Transparent to Translucent |
Luster: |
Vitreous |
Refractive
Index: |
1.677
- 1.718 Biaxial ( - ) |
Birefringence: |
0.041 |
Dispersion: |
Relatively
Weak |
Pleochroism: |
Strong
: Brownish Yellow/ Greenish Yellow
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Occurances
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Geological
Setting: |
In
a huge pale greenish yellow calcite vein associated
with hercynite, magnetite, iron oxides, ferroedenite
hornblende crystals. |
Type
Locality: |
Katukubura
Mountain, Kolonne, Sri Lanka |
Year
Discovered: |
1996 |
View
mineral photos: |
Dunilite
Mineral Photos and Locations |
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More
Information
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Mindat.org
(Olivine) Webmineral.com
(Olivine) |
Dunilite
is a rare member of the Olivine Group that includes
Dunilite,
Fayalite,
Forsterite and
Peridot (Olivine)
although Peridot is not recognized as a separate mineral.
Dunilite
is a very rare and recently discovered variety of Olivine
that was discovered in 1996 in gem gravels at Katukubura Mountain,
Kolonne, Sri
Lanka it was originally thought to be a color variation
of Peridot, and later determined to be a new gem variety.
In addition to the dichroic color differences with Peridot,
the RI values of Dunilite are quite different from those
of Peridot. The GIA issued their report on Dunilite
in 1998.
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Dunilite
gems for sale:

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Gem:
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Dunilite |
Stock
#:
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DUNIL-001 |
Weight:
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0.070
ct |
Size: |
2.46
x 2.22
x 1.48 mm |
Shape: |
Emerald |
Color: |
Olive
Green |
Clarity: |
VSI |
Origin: |
Sri
Lanka |
Treatment: |
None
(natural) |
Price: |
SOLD
(but we have others) |
Pictures
are of the actual gem offered for
sale. Gem images are magnified to
show detail. |
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A
recently discovered (1996) rare gem
from Sri Lanka. This gem is bright green
and well cut.
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