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2 items @ $85.00  

Rare Minerals

Monday, 20 January 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 gold, hemimorphite, kamaishilite, kentbrooksite, landauite, and legrandite and more from places like Shinkolobwe, Katanga, Democratic Republic of Congo, Summit mine, Broadwater Co., Montana, United States, Kamaishi mine, Kamaishi City, Iwate, Japan, Alluaiv Mt., Lovozero Massif, Kola Peninsula, Russia, Burpala alkaline Massif, Eastern-Siberian region, Russia, and Mina Ojuela, Mapimi, Durango, Mexico.

Gold

in Uraninite - #DC64630
Locality
Shinkolobwe, Katanga, Democratic Republic of Congo 
Formula
Au 
Availability
Sold
Size
2 x 2 x 1.5 cm - Thumbnail 
Tagged
native element  
Special Info
Radioactive!! 

Gold grains in black Uraninite.


Gold

Formula
Au 
Crystal System
Isometric 
Crystal Habit
Arborescent, Platy, Granular 
Cleavage
None, None, None 
Luster
Metallic 
Color
yellow, pale yellow, orange, yellow white, reddish white 
Streak
yellow 
Class
Isometric - Hexoctahedral 
Fracture
Hackly 
Hardness
2.5-3 
Collection
Don Cooke Collection
Special Info
Radioactive!!
Mineralpedia
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Hemimorphite

#BAC65302
Locality
Summit mine, Broadwater Co., Montana, United States 
Formula
Zn4Si2O7(OH)2·H2
Availability
Sold
Size
5 x 4 x 2 cm - Miniature 

This is one of the largest Hemimorphite crystals I have ever seen. It has a vitreous luster, much like most smaller Hemimorphite crystals.


Hemimorphite

Formula
Zn4Si2O7(OH)2·H2
Crystal System
Orthorhombic 
Crystal Habit
Massive, Stalactitic, Mammillary 
Cleavage
Perfect, None, None 
Luster
Vitreous (Glassy) 
Color
brown, colorless, greenish gray, yellow brown, white 
Streak
white 
Class
Orthorhombic - Pyramidal 
Fracture
Conchoidal 
Hardness
Collection
William & Anne Cook Collection
SOLD
Kamaishilite - BAC65333
Kamaishilite - BAC65333

Kamaishilite

#BAC65333
Locality
Kamaishi mine, Kamaishi City, Iwate, Japan 
Formula
Ca2(SiAl2)O6(OH)2 
Availability
Sold
Size
0.5 x 0.4 x 0.2 cm - Thumbnail 

Colorless grains to less than 0.2mm in a greenish unknown matrix. 


Kamaishilite

Formula
Ca2(SiAl2)O6(OH)2 
Crystal System
Tetragonal 
Crystal Habit
Microscopic Crystals 
Cleavage
None, None, None 
Luster
Vitreous (Glassy) 
Color
colorless 
Streak
white 
Class
Tetragonal 
Hardness
Collection
William & Anne Cook Collection

Kentbrooksite

#BAC65335
Locality
Alluaiv Mt., Lovozero Massif, Kola Peninsula, Russia 
Formula
(Na,REE)15(Ca,REE)6Mn3Zr3NbSi25O73(O,OH,H2O)3(F,Cl)2 
Availability
Sold
Size
3.5 x 2.3 x 3 cm - Miniature 
Tagged
REE mineral  

Orange partial crystals to 2.5mm.


Kentbrooksite

Formula
(Na,REE)15(Ca,REE)6Mn3Zr3NbSi25O73(O,OH,H2O)3(F,Cl)2 
Crystal System
Trigonal 
Crystal Habit
Anhedral Grains, Aggregates 
Cleavage
None, None, None 
Luster
Vitreous (Glassy) 
Color
yellowish brown 
Streak
white 
Class
Trigonal - Ditrigonal Pyramidal 
Fracture
Brittle - Uneven 
Hardness
5-6 
Collection
William & Anne Cook Collection

Landauite

#BAC65305
Locality
Burpala alkaline Massif, Eastern-Siberian region, Russia 
Formula
(Na,Pb)(Mn2+,Y)(Zn,Fe)2(Ti,Fe3+,Nb)18(O,OH,F)O38 
Availability
Sold
Size
1.5 x 1 x 1 cm - Thumbnail 
Tagged
REE mineral  
Special Info
Type Locality 

Formless micro crystals to less than 0.5mm scattered throughout matix. Landauite is very similar to Chrichtonite of which it is a member of the Chrichtonite group.


Landauite

Formula
(Na,Pb)(Mn2+,Y)(Zn,Fe)2(Ti,Fe3+,Nb)18(O,OH,F)O38 
Crystal System
Trigonal 
Crystal Habit
Prismatic, Irregular Grains, Aggregates 
Cleavage
None, None, None 
Luster
Sub Metallic 
Color
black 
Streak
gray 
Class
Trigonal - Rhombohedral 
Fracture
Conchoidal 
Hardness
7.5 
Collection
William & Anne Cook Collection
Special Info
Type Locality

Legrandite

with Adamite - #BAC65349
Locality
Mina Ojuela, Mapimi, Durango, Mexico 
Formula
Zn2AsO4(OH)·H2
Availability
Available
Price
$175.00
Size
6 x 4.5 x 5 cm - Sm Cabinet 
Tagged
arsenate  

Adamite with Legrandite is not a typical association. The Adamite on this specimen light yellow with colorless tips. The Legrandite crystals are up to 4mm.


Legrandite

Formula
Zn2AsO4(OH)·H2
Crystal System
Monoclinic 
Crystal Habit
Crystalline - Fine, Prismatic 
Cleavage
Imperfect, None, None 
Luster
Vitreous (Glassy) 
Color
yellow, yellowish orange 
Streak
white 
Class
Monoclinic - Prismatic 
Fracture
Brittle - Conchoidal 
Hardness
4-5 
Collection
William & Anne Cook Collection

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