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Recently Released New Additions

Rare Minerals

Sunday, 16 April 2023 06:00 PM

Introducing the "Rare Minerals" gallery which is part of our New Additions galleries. This gallery contains mineral specimens for sale including geffroyite, kolwezite, mckelveyite-(y), and meurigite-k and more from places like San Miguel mine, Moctezuma, Sonora, Mexico, Mupine mine, Kamoto, Kolwezi dist., DR Congo, Mont Saint-Hilaire, Montérégie, Québec, Canada, and Hagendorf-Süd, Oberpfälzer Wald, Bavaria, Germany.

Geffroyite - BAC61507
Geffroyite - BAC61507

Geffroyite

#BAC61507
Locality
San Miguel mine, Moctezuma, Sonora, Mexico 
Formula
(Cu,Fe,Ag)9Se8 
Availability
Available
Price
$75.00
Size
2.3 x 2 x 1.4 cm - Thumbnail 
Tagged
copper , selenium , silver  

Silvery crystal grains to 0.5mm and in aggregates to around 2mm. The Geffroyite is scattered throughout the matrix not just the arrowed areas.


Geffroyite

Formula
(Cu,Fe,Ag)9Se8 
Crystal System
Isometric 
Luster
Metallic 
Color
bronze brown 
Class
Isometric - Hexoctahedral 
Hardness
2.5 
Collection
William & Anne Cook Collection
Mineralpedia
View Geffroyite
On Dakota Matrix
Previously Sold Geffroyite
On Dakota Matrix
Other Available Geffroyite
WebMineral
View Geffroyite
Mindat
View Geffroyite
Kolwezite - BAC61450
Kolwezite - BAC61450

Kolwezite

#BAC61450
Locality
Mupine mine, Kamoto, Kolwezi dist., DR Congo 
Formula
CuCoCO3(OH)2 
Availability
Available
Price
$275.00
Size
7.5 x 5.5 x 2.5 cm - Sm Cabinet 
Tagged
carbonate , copper , cobalt  

A large vug 3 x 1.5cm filled with fuzzy or velvety looking green Kolwezite. In-hand the Kolwezite is more of an olive color. Exceptional specimen for a fairly rare mineral found in basically six worldwide deposits.


Kolwezite

Formula
CuCoCO3(OH)2 
Crystal System
Triclinic 
Crystal Habit
Nodular, Encrustations 
Luster
Vitreous (Glassy) 
Color
beige brown, green, black 
Streak
beige 
Class
Triclinic 
Hardness
4 
Collection
William & Anne Cook Collection
Mineralpedia
View Kolwezite
On Dakota Matrix
Previously Sold Kolwezite
On Dakota Matrix
Other Available Kolwezite
WebMineral
View Kolwezite
Mindat
View Kolwezite
Mckelveyite-(Y) - BAC61458
Mckelveyite-(Y) - BAC61458

Mckelveyite-(Y)

#BAC61458
Locality
Mont Saint-Hilaire, Montérégie, Québec, Canada 
Formula
NaBa3(Ca,U)Y(CO3)6·3H2O 
Availability
Available
Price
$125.00
Size
4 x 3 x 2 cm - Miniature 
Tagged
carbonate , REE mineral  

Interesting yellowish crystals forming saucer-like stacked groups to 1mm in Albite and Phlogopite matrix.


Mckelveyite-(Y)

Formula
NaBa3(Ca,U)Y(CO3)6·3H2O 
Crystal System
Monoclinic 
Crystal Habit
Pyramidal 
Cleavage
Indistinct, None, None 
Luster
Vitreous (Glassy) 
Color
yellow, black, greenish gray, white, gray 
Streak
white 
Class
Monoclinic - Domatic 
Hardness
3.5-4 
Collection
William & Anne Cook Collection
Mineralpedia
View Mckelveyite-(Y)
On Dakota Matrix
Previously Sold Mckelveyite-(Y)
On Dakota Matrix
Other Available Mckelveyite-(Y)
WebMineral
View Mckelveyite-(Y)
Mindat
View Mckelveyite-(Y)
Meurigite-K - BAC61506
Meurigite-K - BAC61506

Meurigite-K

#BAC61506
Locality
Hagendorf-Süd, Oberpfälzer Wald, Bavaria, Germany 
Formula
[K(H2O)2.5][Fe3+8(PO4)6(OH)7]·4H2O 
Availability
Available
Price
$45.00
Size
2 x 1.5 x 1.6 cm - Thumbnail 
Tagged
phosphate  

Tiny radiating mustard yellow crystals in an area of 5 x 3mm enclosed in what looks like Rockbridgeite.


Meurigite-K

Formula
[K(H2O)2.5][Fe3+8(PO4)6(OH)7]·4H2O 
Crystal System
Monoclinic 
Crystal Habit
Tabular, Spherical 
Cleavage
Good, None, None 
Luster
Silky 
Color
white, cream, yellowish brown, pale yellow, canary yellow 
Streak
pale yellowish white 
Class
Monoclinic - Prismatic 
Hardness
3 
Collection
William & Anne Cook Collection
Mineralpedia
View Meurigite-K
On Dakota Matrix
Previously Sold Meurigite-K
On Dakota Matrix
Other Available Meurigite-K
WebMineral
View Meurigite-K
Mindat
View Meurigite-K

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