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Click on a
letter above to view the list of gems. |
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| Tugtupite is named after its discovery
locality,
Tugtup agtakôrfia, Tunugdliarfik, Greenland.
| Discovered
in 1957; IMA
status: Valid (IMA approved 1962) |
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Chemistry
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Chemical
Formula: |
Na4AlBeSi4O12Cl
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Sodium
Aluminum Berylium Silicate Chloride |
Molecular
Weight: |
467.74 gm
|
Composition: |
Sodium |
19.66 % |
Na |
26.50 % |
Na2O |
|
Beryllium |
1.93 % |
Be |
5.35 % |
BeO |
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Aluminum |
5.77 % |
Al |
10.90 % |
Al2O3 |
|
Silicon |
24.02 % |
Si |
51.38 % |
SIO2 |
|
Chlorine |
7.58 % |
Cl |
7.58 % |
Cl |
|
— |
—
% |
Cl |
-1.71 % |
-O=Cl2 |
|
Oxygen |
41.05 % |
O |
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|
100.00 % |
|
100.00 % |
= TOTAL OXIDE |
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Classification
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Mineral
Classification: |
Silicates
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Strunz 8th
Ed. ID:
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8/J.11-50
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Nickel-Strunz 10th
Ed. ID:
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9.FB.10
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9 : SILICATES (Germanates)
F : Tektosilicates without zeolitic H2O
B : Tektosilicates with additional anions
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Related
to: |
Helvine
Group.
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Members
of Group: |
Helvine
Group: Danalite, Genthelvite, Helvine, Tugtupite
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Varieties: |
None
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Synonyms: |
Helvite,
Moonlight Garnet, Tetrahedral Garnet
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Crystal
Data
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Crystallography:
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Tetragonal
- Disphenoidal
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Crystal
Habit:
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Crystals are short
tetragonal prisms with pyramids, sphenoids, and bisphenoids,
to 3 mm; fine-grained aggregates, massive.
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Twinning:
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Penetration
twinning produces pseudocubic triplets; pseudotrigonal
contact twins with composition planes.
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Physical
Properties
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Cleavage: |
Distinct
on [101], Fair on [110]
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Fracture: |
Conchoidal
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Tenacity:
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Brittle
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Moh's
Hardness: |
4.0
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Density:
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2.33 (g/cm3)
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Luminescence:
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Fluorescent;
bright orange under LW UV. Phosphorescent red to
rose-pink under UV; photochromic, pale colors become
deep pink on exposure to sunlight or X-rays. |
Radioactivity:
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Not
Radioactive
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Other: |
Piezoelectric
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Optical
Properties
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Color: |
White,
Pink, Crimson, Blue, Green |
Transparency: |
Opaque,
Translucent, Transparent |
Luster: |
Vitreous
to Greasy |
Refractive
Index: |
1.492
- 1.502 Uniaxial ( + ); anomalously Biaxial |
Birefringence: |
0.0060
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Dispersion: |
0.012
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Pleochroism: |
Weak
Lilac to weak Red-Orange
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Occurances
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Geological
Setting: |
Replaces
chkalovite in hydrothermal veins cutting sodalite syenite
and syenite (Ilimaussaq intrusion, Greenland); an alteration
product in pegmatites in a differentiated alkalic massif
(Lovozero massif, Russia). |
Common
Associations: |
Albite,
Analcime, Aegirine, Natrolite, Tetranatrolite, Chkalovite,
Lithian mica, Epistolite, Niobophyllite, Monazite, Rhabdophane,
Gerasimovskite, Nenadkevichite, Beryllite |
Common
Impurities: |
Fe,
Ga, Mg, Ca, K, H2O,
S |
Type
Locality: |
Tugtup agtakôrfia, Ilimaussaq complex, Narsaq, Kitaa
(West Greenland) Province, Greenland |
Year
Discovered: |
1957
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View
mineral photos: |
Tugtupite
Mineral Photos and Locations |
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More
Information
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Mindat.org
Webmineral.com
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Tugtupite is a rare
member of the Helvine
Group
of minerals that includes Danalite, Genthelvite. Helvine and Tugtupite. Tugtupite was discovered in Tugtup agtakôrfia, Tunugdliarfik,
Greenland in 1962. It is also known as Reindeer Stone
because Tugtup means reindeer. Most material is opaque
to translucent
and used for cabochons. Transparent material is rarely
available and cut into very small faceted gems. These
are very rare and usually slightly to moderately included.
Tugtupite has an unusual characteristic in that it darkens
in color when exposed to UV light and then slowly lightens
back up. Tugtupite is also fluorescent exhibiting bright orange under longwave UV
light. If you hover your cursor over the Tugtupite
picture at the top of this page you will see the Tugtupite
gem exhibiting it bright orange color under longwave
UV light.
The
main sources of Tugtupite are Tasseq Slope, Ilimaussaq
complex, Narsaq, Kitaa Province, Greenland; and minor
occurances at Kola Peninsula Russia and Mont Saint-Hilaire,
Quebec, Canada.
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Tugtupite
gems for sale:
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Gem:
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Tugtupite |
Stock
#:
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TUGT-001 |
Weight:
|
0.0210
ct |
Size: |
1.99
x 1.04 mm |
Shape: |
Round |
Color: |
Light
Pink |
Clarity: |
Eye
Clean |
Origin: |
Narsaq,
Greenland |
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
rare gem not normally seen transparent
- not to mention eye clean! A very well
faceted gem for such a small size. It
glows bright pink under LW UV
and it phosphoresces pale greenish in
the dark after SW UV exposure.
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|
Gem:
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Tugtupite |
Stock
#:
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TUGT-002 |
Weight:
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11.5325
ct |
Size: |
25.02
x 18.13
x 5.08 mm |
Shape: |
Triangle
Cabochon |
Color: |
Pink |
Clarity: |
Opaque |
Origin: |
Narsaq,
Greenland |
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. |
|
|
A
rare and large gem from Greenland. The second picture shows it glowing
bright orange-pink under LW UV and it phosphoresces pale
greenish in the dark after SW UV
exposure. It also turns darker red after
UV exposure.
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|
Gem:
|
Tugtupite |
Stock
#:
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TUGT-003 |
Weight:
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2.2115
ct |
Size: |
9.69
x 8.19
x 3.77 mm |
Shape: |
Oval
Cabochon |
Color: |
Pink |
Clarity: |
Translucent |
Origin: |
Narsaq,
Greenland |
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. |
|
|
A
rare gem not normally seen this translucent.
The second picture shows it glowing
bright orange-pink under LW UV and it phosphoresces pale
greenish in the dark after SW UV
exposure. It also turns darker red after
UV exposure.
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Gem:
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Tugtupite |
Stock
#:
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TUGT-004 |
Weight:
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6.0560
ct |
Size: |
18.15
x 14.65
x 4.24 mm |
Shape: |
Triangle
Cabochon |
Color: |
Pink
& White |
Clarity: |
Opaque |
Origin: |
Narsaq,
Greenland |
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. |
|
|
A
rare and large gem from Greenland. The second picture shows it glowing
bright orange-pink under LW UV and it phosphoresces pale
greenish in the dark after SW UV
exposure. It also turns darker red after
UV exposure.
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