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Rare Minerals

Friday, 23 June 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 georgechaoite, kobokoboite, malhmoodite, montgomeryite, nadorite, and nepouite and more from places like Wind Mountain, Otero Co., New Mexico, United States, Kobokobo Pegmatite, Sud-Kivu, Democratic Republic of Congo, Wilson Springs, Garland Co., Arkansas, United States, Tip Top mine, Custer Co., South Dakota, United States, Djebel Nador, Constantine prov., Algeria, and Bon Accord, Barberton dist., Mpumalanga prov., South Africa.

Georgechaoite

#BAC61843
Locality
Wind Mountain, Otero Co., New Mexico, United States 
Formula
KNaZrSi3O9·2H2
Availability
Available
Price
$150.00
Size
1 x 0.9 x 0.6 cm - Thumbnail 
Special Info
Type Locality 

White prismatic crystals to 5mm.


Georgechaoite

Formula
KNaZrSi3O9·2H2
Crystal System
Orthorhombic 
Cleavage
None, None, None 
Color
colorless, white 
Streak
white 
Class
Orthorhombic - Pyramidal 
Fracture
Conchoidal 
Hardness
Collection
William & Anne Cook Collection
Special Info
Type Locality

Kobokoboite

#61864
Locality
Kobokobo Pegmatite, Sud-Kivu, Democratic Republic of Congo 
Formula
Al6(PO4)4(OH)6·11H2
Availability
Available
Price
$1,750.00
Size
2.5 x 2 x 1.5 cm - Thumbnail 
Tagged
phosphate  
Special Info
Type Locality 

Very rich specimen full of pearly white flakes and spheroids of extremely rare Kobokoboite. This is the type locality of three worldwide localities.


Special Info
Type Locality

Malhmoodite

#BAC61861
Locality
Wilson Springs, Garland Co., Arkansas, United States 
Formula
Fe2+Zr(PO4)2·4H2
Availability
Available
Price
$40.00
Size
Micromount 
Tagged
phosphate  
Special Info
Type Locality 

Three tiny beige balls of Malhmoodite in micromount box.


Malhmoodite

Formula
Fe2+Zr(PO4)2·4H2
Crystal System
Monoclinic 
Cleavage
Good, None, None 
Luster
Silky 
Color
cream white 
Streak
white 
Class
Monoclinic - Prismatic 
Hardness
Collection
William & Anne Cook Collection
Special Info
Type Locality

Montgomeryite

with Robertsite - #61867
Locality
Tip Top mine, Custer Co., South Dakota, United States 
Formula
Ca4MgAl4(PO4)6(OH)4·12H2
Availability
Available
Price
$3,500.00
Size
4.5 x 3 x 1 cm - Miniature 
Tagged
phosphate , pegmatite mineral  

This is one of the best specimens of Montgomeryite I have seen. The crystals are well defined, distinct and vibrant. Both sides are covered with the bright red crystals. Red Montgomeryite is only found at two localities: the Tip Top mine and the White Elephant in the Black mining Hills of Dakota (to quote the Beatle song Rocky Racoon). The White Elephant Montgomeryite, doesn't compare to the Tip Top. There is a little black Robertsite on the specimen (forth and fifth photos). 


Montgomeryite

Formula
Ca4MgAl4(PO4)6(OH)4·12H2
Crystal System
Monoclinic 
Cleavage
Perfect, Indistinct, None 
Luster
Vitreous (Glassy) 
Color
colorless, yellowish, white, green, red 
Streak
white 
Class
Monoclinic - Prismatic 
Hardness

Nadorite

#54701
Locality
Djebel Nador, Constantine prov., Algeria 
Formula
PbSb3+O2Cl 
Availability
Available
Price
$3,750.00
Size
7 x 5 x 3 cm - Sm Cabinet 
Special Info
Antique Specimen 

Smoky brown, translucent crystal plates measuring 7mm on edge. This is an antique specimen once in the collection of Emile Bertrand circa 1890's. Betrand was an early pioneer in the study of optical mineralogy and introduced the "Betrand" lens to the petrology microscope. He was one of the founders of the French Mineralogy Society and went to school at the Paris School of Mines. Please see the Mineralogical Record label archive for more information (click here) . 

Betrand's label along with a few other labels are shown in the provenance tab.


Nadorite

Formula
PbSb3+O2Cl 
Crystal System
Orthorhombic 
Cleavage
Perfect, None, None 
Luster
Adamantine - Resinous 
Color
brown, brownish yellow, grayish brown, yellow 
Streak
yellow white 
Class
Orthorhombic - Dipyramidal 
Fracture
Brittle 
Hardness
3.5-4 
Collection
Willard L. Roberts Collection
Special Info
Antique Specimen
Mineralpedia
View Nadorite
On Dakota Matrix
Previously Sold Nadorite
On Dakota Matrix
Other Available Nadorite
WebMineral
View Nadorite
Mindat
View Nadorite

Nepouite

with Trevorite - #BAC61858
Locality
Bon Accord, Barberton dist., Mpumalanga prov., South Africa 
Formula
Ni3Si2O5(OH)4 
Availability
Available
Price
$85.00
Size
3.5 x 2 x 1.4 cm - Miniature 
Tagged
nickel  

Waxy deep green Nepouite at the red arrow and other places on the specimen with black, granular Trevorite (last three photos). There is probably other species in the specimen.


Nepouite

Formula
Ni3Si2O5(OH)4 
Crystal System
Orthorhombic 
Crystal Habit
Platy, Pseudo Hexagonal 
Cleavage
Good, Good, None 
Luster
Vitreous - Pearly 
Color
pale green, deep green 
Streak
greenish white 
Class
Orthorhombic - Pyramidal 
Hardness
2-2.5 
Collection
William & Anne Cook Collection
On Dakota Matrix
Previously Sold Nepouite
On Dakota Matrix
Other Available Nepouite
WebMineral
View Nepouite
Mindat
View Nepouite

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