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Rare & Mixed Minerals

Monday, 08 August 2022 06:00 PM

Introducing the "Rare & Mixed Minerals" gallery which is part of our New Additions galleries. This gallery contains mineral specimens for sale including beryl, cornwallite, hydrohetaerolite, margarite, marinellite, and mimetite and more from places like Bennett quarry, Buckfield, Oxford Co., Maine, United States, J.R. Robertson claim, Yavapai Co., Arizona, United States, Wolftone mine, Leadville, Lake Co., Colorado, Chester Emery mines, Hampden Co., Massachusetts, United States, Magliano Romano, Rome Capital, Lazio, Italy, and Tsumeb mine, Tsumeb, Namibia.

Beryl

var. cesium - #BW59009
Locality
Bennett quarry, Buckfield, Oxford Co., Maine, United States 
Formula
Be3Al2Si6O18 
Availability
Available
Price
$35.00
Size
4 x 4.5 x 1.3 cm - Miniature 
Tagged
beryllium  

Pink cesium bearing Beryl mass.


Beryl

Formula
Be3Al2Si6O18 
Crystal System
Hexagonal 
Crystal Habit
Crystalline - Coarse, Prismatic, Columnar 
Cleavage
Imperfect, None, None 
Luster
Vitreous - Resinous 
Color
green, blue, yellow, colorless, pink 
Streak
white 
Class
Hexagonal - Dihexagonal Dipyramidal 
Fracture
Brittle - Conchoidal 
Hardness
7.5-8 
Collection
Bill Wilson Collection
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Previously Sold Beryl
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Cornwallite

#BW58963
Locality
J.R. Robertson claim, Yavapai Co., Arizona, United States 
Formula
Cu5(AsO4)2(OH)4 
Availability
Sold
Size
5.5 x 4 x 2.6 cm - Sm Cabinet 
Tagged
arsenate , copper  

Light green spheroidal crystals in vugs and crusts.


Cornwallite

Formula
Cu5(AsO4)2(OH)4 
Crystal System
Monoclinic 
Crystal Habit
Massive, Radial, Encrustations 
Cleavage
None, None, None 
Luster
Earthy (Dull) 
Color
light green, dark green, black green 
Streak
apple green 
Class
Monoclinic - Prismatic 
Fracture
Conchoidal 
Hardness
4-5 
Collection
Bill Wilson Collection

Hydrohetaerolite

#RS59008
Locality
Wolftone mine, Leadville, Lake Co., Colorado 
Formula
Zn2Mn3+4O8·H2
Availability
Available
Price
$30.00
Size
6 x 5.5 x 3.5 cm - Sm Cabinet 

Black crystalline masses sparse in matrix. It is a locality specimn.


Hydrohetaerolite

Formula
Zn2Mn3+4O8·H2
Crystal System
Tetragonal 
Crystal Habit
Radial, Botryoidal, Massive 
Cleavage
Good, None, None 
Luster
Sub Metallic 
Color
brownish black, dark brown 
Streak
dark brown 
Class
Tetragonal - Ditetragonal Dipyramidal 
Hardness
5-6 
Collection
RC Stamberg Collection

Margarite

#RS58934
Locality
Chester Emery mines, Hampden Co., Massachusetts, United States 
Formula
CaAl2(Si2Al2)O10(OH)2 
Availability
Sold
Size
6 x 3 x 3 cm - Sm Cabinet 

Pinkish and silvery foliated plates of Margarite to 3cm. Margarite is a member of the mica group, and this is a classic and one of the better localities for the mineral. Margarite is found with emery in low grade metamorphic environments.


Margarite

Formula
CaAl2(Si2Al2)O10(OH)2 
Crystal System
Monoclinic 
Crystal Habit
Lamellar, Massive - Lamellar, Scaly 
Cleavage
Good, None, None 
Luster
Pearly 
Color
white, gray, pinkish gray, yellowish gray 
Streak
white 
Class
Monoclinic - Prismatic 
Fracture
Brittle 
Hardness
Collection
RC Stamberg Collection
Mineralpedia
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Marinellite

with Sanidine - #BW59000
Locality
Magliano Romano, Rome Capital, Lazio, Italy 
Formula
Na42Ca6Al36Si36O144(SO4)8Cl2·6H2
Availability
Sold
Size
2 x 2 x 1 cm - Thumbnail 

Light blue translucent crystal grains from 2 to 4mm in matrix with some biotite and other minerals. Marinellite is a Cancrinite group minerals, which are silica deficient. It is formed as ejected volcanic rock. It is a rich specimen and this locality is one of three worldwide.


Marinellite

Formula
Na42Ca6Al36Si36O144(SO4)8Cl2·6H2
Crystal System
Trigonal 
Crystal Habit
Anhedral Grains 
Cleavage
Poor, None, None 
Luster
Vitreous (Glassy) 
Color
colorless 
Streak
white 
Class
Trigonal 
Fracture
Brittle - Conchoidal 
Hardness
5.5 

Mimetite

with Duftite(?) - #RS58928
Locality
Tsumeb mine, Tsumeb, Namibia 
Formula
Pb5(AsO4)3Cl 
Availability
Available
Price
$75.00
Size
5 x 4 x 2 cm - Miniature 
Tagged
arsenate  

A colorful Mimetite specimen with a red coating on half of the crystals and the remainder being your typical yellow. Many of the crystals show an incredible six-sided pyramidal termination. Hidden near the top edge of the specimen are granular Duftite(?) crystals. The Duftite is barely seen in hand not because of the size, but because of the color. The digital camera enhances the green.


Mimetite

Formula
Pb5(AsO4)3Cl 
Crystal System
Hexagonal 
Crystal Habit
Reniform, Globular, Prismatic 
Cleavage
Imperfect, None, None 
Luster
Adamantine - Resinous 
Color
white, yellow, orange, brown, red 
Streak
white 
Class
Hexagonal - Dipyramidal 
Fracture
Brittle - Conchoidal 
Hardness
3.5-4 
Collection
RC Stamberg Collection
Mineralpedia
View Mimetite
On Dakota Matrix
Previously Sold Mimetite
On Dakota Matrix
Other Available Mimetite
WebMineral
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Mindat
View Mimetite

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