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0 item @ $0.00  

Mixed Minerals

Sunday, 11 July 2021 06:00 PM

Introducing the "Mixed Minerals" gallery which is part of our New Additions galleries. This gallery contains mineral specimens for sale including quartz, siderite, strengite, sylvanite, and topaz and more from places like Gravel Hill mine, Perranzabuloe, Cornwall, England, Eagle mine, Gilman, Eagle Co., Colorado, United States, Kobokobo Pegmatite, Sud-Kivu, Democratic Republic of Congo, Spotted Horse mine, Fergus Co., Montana, United States, and Ouro Preto, Minas Gerais, Brazil.

Quartz

ps after Baryte - #54518
Locality
Gravel Hill mine, Perranzabuloe, Cornwall, England 
Formula
SiO2 
Availability
Sold
Size
6 x 4 x 4 cm - Sm Cabinet 

An interesting specimen of former Baryte crystals from 1 to 6mm now replaced by Quartz.


Quartz

Formula
SiO2 
Crystal System
Trigonal 
Crystal Habit
Crystalline - Coarse, Druse, Crystalline - Fine 
Cleavage
Indistinct, None, None 
Luster
Vitreous (Glassy) 
Color
brown, colorless, violet, gray, yellow 
Streak
white 
Class
Trigonal - Trapezohedral 
Fracture
Conchoidal 
Hardness
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Siderite

with Pyrite - #AH56031
Locality
Eagle mine, Gilman, Eagle Co., Colorado, United States 
Formula
FeCO3 
Availability
Sold
Size
5 x 4.5 x 1.5 cm - Miniature 
Tagged
carbonate  

Brown disc-like crystals of Siderite to 5mm with a lot of Pyrite crystals to about 1mm and less.


Siderite

Formula
FeCO3 
Crystal System
Trigonal 
Crystal Habit
Tabular, Massive, Botryoidal 
Cleavage
Perfect, Perfect, Perfect 
Luster
Vitreous (Glassy) 
Color
yellowish brown, brown, gray, yellowish gray, greenish gray 
Streak
white 
Class
Trigonal - Hexagonal Scalenohedral 
Fracture
Brittle - Conchoidal 
Hardness
3.5 
Collection
Arnold G Hampson Collection
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Strengite

#BN56074
Locality
Kobokobo Pegmatite, Sud-Kivu, Democratic Republic of Congo 
Formula
Fe3+PO4·2H2
Availability
Sold
Size
7 x 6.5 x 3 cm - Sm Cabinet 
Tagged
phosphate , pegmatite mineral  

Granular purple Srengite in a phosphate nodule with Rockbridgeite and Mitridatite.


Strengite

Formula
Fe3+PO4·2H2
Crystal System
Orthorhombic 
Crystal Habit
Spherical, Radial, Botryoidal 
Cleavage
Good, Poor, None 
Luster
Vitreous (Glassy) 
Color
colorless, pale violet, deep violet, red, carmine red 
Streak
white 
Class
Orthorhombic - Dipyramidal 
Fracture
Brittle - Conchoidal 
Hardness
3.5 
Collection
Dr. Buford Nichols Collection
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Sylvanite

with Pyrite & Fluorite - #47836
Locality
Spotted Horse mine, Fergus Co., Montana, United States 
Formula
AgAuTe4 
Availability
Sold
Size
5 x 3 x 1.5 cm - Miniature 
Tagged
tellurium , silver , gold  

Rich specimen of crystal blades of Sylvanite to 2mm in Flourite. They are not readily apparent but can be seen when the specimen is tilted at the right angles to see a goldish flash. A difficult locality to obtain. The locality is not well-known and specimens are hard to find.


Sylvanite

Formula
AgAuTe4 
Crystal System
Monoclinic 
Crystal Habit
Prismatic, Skeletal, Platy 
Cleavage
Perfect, None, None 
Luster
Metallic 
Color
yellowish silver white, white 
Streak
steel gray 
Class
Monoclinic - Prismatic 
Fracture
Uneven 
Hardness
1.5-2 
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Sylvanite

#56060
Locality
Spotted Horse mine, Fergus Co., Montana, United States 
Formula
AgAuTe4 
Availability
Sold
Size
4.5 x 3 x 2 cm - Miniature 
Tagged
tellurium , silver , gold  

Elongated crystal blades from 1 to 4mm in Fluorite. Fairly rich.


Sylvanite

Formula
AgAuTe4 
Crystal System
Monoclinic 
Crystal Habit
Prismatic, Skeletal, Platy 
Cleavage
Perfect, None, None 
Luster
Metallic 
Color
yellowish silver white, white 
Streak
steel gray 
Class
Monoclinic - Prismatic 
Fracture
Uneven 
Hardness
1.5-2 
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Topaz

(Imperial) - #BN55816
Locality
Ouro Preto, Minas Gerais, Brazil 
Formula
Al2SiO4F2 
Availability
Sold
Size
3.5 x 1 x 0.7 cm - Miniature 

Gemmy, striated, orange imperial Topaz with a good termination. Excellent gem specimen.


Topaz

Formula
Al2SiO4F2 
Crystal System
Orthorhombic 
Crystal Habit
Crystalline - Coarse, Prismatic, Massive - Granular 
Cleavage
Perfect, None, None 
Luster
Vitreous (Glassy) 
Color
colorless, pale blue, yellow, yellowish brown, red 
Streak
white 
Class
Orthorhombic - Dipyramidal 
Fracture
Brittle - Uneven 
Hardness
Collection
Dr. Buford Nichols Collection
Mineralpedia
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