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1 item @ $25.00  

Rare Minerals

Friday, 07 March 2025 06:00 PM

Introducing the "Rare Minerals" gallery which is part of our New Additions galleries. This gallery contains mineral specimens for sale including bornite, gerhardtite, mountkeithite, schwartzembergite, and stromeyerite and more from places like Carn Brea, Redruth, Cornwall, England, Likasi mine, Katanga, Democratic Republic of Congo, MKD5 Ni deposit, Mt. Keith, Western Australia, Australia, San Francisco mine, Sierra Gorda dist., Antofagasta, Chile, and Alexander mine, Vrančice, Příbram, Bohemia, Czech Republic.

Bornite

#65517
Locality
Carn Brea, Redruth, Cornwall, England 
Formula
Cu5FeS4 
Availability
Available
Price
$495.00
Size
6 x 4.5 x 4 cm - Sm Cabinet 
Tagged
sulfide , copper  

Iridescent blue Bornite crystals from important Cornish mine.


Bornite

Formula
Cu5FeS4 
Crystal System
Orthorhombic 
Crystal Habit
Massive - Granular, Reniform, Granular 
Cleavage
Imperfect, None, None 
Luster
Metallic 
Color
copper red, bronze brown, purple 
Streak
grayish black 
Class
Orthorhombic - Dipyramidal 
Fracture
Conchoidal 
Hardness
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Gerhardtite

#65610
Locality
Likasi mine, Katanga, Democratic Republic of Congo 
Formula
Cu2NO3(OH)3 
Availability
Available
Price
$45.00
Size
Capsule 
Tagged
copper  

Cobalt blue acicular crystals 3mm.


Gerhardtite

Formula
Cu2NO3(OH)3 
Crystal System
Orthorhombic 
Cleavage
Perfect, Good, None 
Luster
Vitreous (Glassy) 
Color
green, dark green 
Streak
light green 
Class
Orthorhombic - Disphenoidal 
Hardness

Mountkeithite

#65465
Locality
MKD5 Ni deposit, Mt. Keith, Western Australia, Australia 
Formula
Mg11Fe3+3(SO4)3.5(OH)24·11H2
Availability
Available
Price
$40.00
Size
1.2 x 0.6 x 0.4 cm - Thumbnail 
Special Info
Type Locality 

Purple grains in serpentine matrix to 1mm.


Mountkeithite

Formula
Mg11Fe3+3(SO4)3.5(OH)24·11H2
Crystal System
Hexagonal 
Crystal Habit
Flakes, Granular, Rosette 
Cleavage
Perfect, None, None 
Luster
Pearly 
Color
white, light pink 
Streak
white 
Class
Hexagonal 
Hardness
Special Info
Type Locality

Schwartzembergite

#65652
Locality
San Francisco mine, Sierra Gorda dist., Antofagasta, Chile 
Formula
Pb2+5H2I3+O6Cl3 
Availability
Available
Price
$55.00
Size
2.3 x 1.6 x 1.6 cm - Thumbnail 

Yellow platey crystals to 1mm.


Schwartzembergite

Formula
Pb2+5H2I3+O6Cl3 
Crystal System
Tetragonal 
Crystal Habit
Druse, Crystalline - Fine 
Cleavage
Distinct, None, None 
Luster
Adamantine 
Color
yellow brown, light yellow, reddish brown 
Streak
light yellow 
Class
Tetragonal - Ditetragonal Dipyramidal 
Hardness
2.5 

Stromeyerite

#65538
Locality
Alexander mine, Vrančice, Příbram, Bohemia, Czech Republic 
Formula
CuAgS 
Availability
Available
Price
$350.00
Size
6.5 x 4 x 1.5 cm - Sm Cabinet 
Tagged
sulfide , copper , silver  

Crude dull grey crystals and masses of rare Stromeyerite.


Stromeyerite

Formula
CuAgS 
Crystal System
Orthorhombic 
Crystal Habit
Granular, Massive, Pseudo Hexagonal 
Cleavage
None, None, None 
Luster
Metallic 
Color
blue gray, dark blue, dark steel gray, steel gray 
Streak
steel gray 
Class
Orthorhombic - Dipyramidal 
Fracture
Conchoidal 
Hardness
2.5-3 

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