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Recently Released New Additions

New Additions

Sunday, 22 October 2023 06:00 PM

Introducing the "New Additions" gallery which is part of our New Additions galleries. This gallery contains mineral specimens for sale including domeykite, labuntsovite-mg, peprossiite-(ce), sigloite, spencerite, and valentinite and more from places like Cashin mine, Montrose Co., Colorado, United States, Kovdor Zheleznyi mine, Kovdor Massif, Murmansk Oblast, Russia, Capranica, near Viterbo, Lazio, Italy, Siglo Veinte mine, Llallagua, Bolivia, Hudson Bay mine, Salmo, British Columbia, Canada, and San José mine, Oruro City, Oruro Dept., Bolivia.

SOLD
Domeykite - BAC62654
Domeykite - BAC62654

Domeykite

with Copper - #BAC62654
Locality
Cashin mine, Montrose Co., Colorado, United States 
Formula
Cu3As 
Availability
Sold
Size
7.5 x 4.5 x 2 cm - Sm Cabinet 
Tagged
copper  

This is weird, but interesting specimen and is definitely an old-timer from the Cashin mine in Colorado. The Cashin mine is located in the La Sal Creek district near the Cliff Dweller mine in Montrose county. Reports show that ore produced prior to 1920 contained 35 to 50% Copper and 8-10 ounces of Silver per ton. This specimen is composed of Copper and Domeykite and probably a lot of Silver. Some parts are harder (3.5) and when scratched show a silvery luster, which is the Domeykite. Other parts show a copper luster and is obviously softer and malleable. Silver is also seen when scratched. I am inclined to think this specimen is a mixture of the three minerals much like an alloy. There are areas where nice but mal-formed crystals of Copper can be seen.


Domeykite

Formula
Cu3As 
Crystal System
Isometric 
Crystal Habit
Botryoidal, Reniform, Massive 
Cleavage
None, None, None 
Luster
Metallic 
Color
gray, yellow brown, silver white, tin white 
Streak
black gray 
Class
Isometric - Hextetrahedral 
Fracture
Brittle - Sectile 
Hardness
3-3.5 
Collection
Chet S. Lemanski, Jr. Collection
On Dakota Matrix
Previously Sold Domeykite
On Dakota Matrix
Other Available Domeykite
WebMineral
View Domeykite
Mindat
View Domeykite
Labuntsovite-Mg - BAC62643
Labuntsovite-Mg - BAC62643

Labuntsovite-Mg

#BAC62643
Locality
Kovdor Zheleznyi mine, Kovdor Massif, Murmansk Oblast, Russia 
Formula
Na4K4Mg2Ti8O4(Si4O12)4(OH)4·10-12H2O 
Availability
Available
Price
$60.00
Size
4 x 3 x 3 cm - Miniature 

Glassy bright orange crystals in Albite mass.


Labuntsovite-Mg

Formula
Na4K4Mg2Ti8O4(Si4O12)4(OH)4·10-12H2O 
Crystal System
Monoclinic 
Crystal Habit
Prismatic, Radial, Aggregates 
Cleavage
Imperfect, Imperfect, None 
Luster
Vitreous (Glassy) 
Color
colorless, yellowish white, pink, light orange 
Streak
white 
Class
Monoclinic - Prismatic 
Fracture
Stepped 
Hardness
5 
Collection
William & Anne Cook Collection
On Dakota Matrix
Previously Sold Labuntsovite-Mg
On Dakota Matrix
Other Available Labuntsovite-Mg
WebMineral
View Labuntsovite-Mg
Mindat
View Labuntsovite-Mg
Peprossiite-(Ce) - BAC62628
Peprossiite-(Ce) - BAC62628

Peprossiite-(Ce)

#BAC62628
Locality
Capranica, near Viterbo, Lazio, Italy 
Formula
CeAl2B4O10 
Availability
Available
Price
$65.00
Size
1.5 x 1 x 0.8 cm - Thumbnail 
Tagged
REE mineral  

Yellow bladed crystals with colorless Sanidine and blue Cancrinite(?).


Peprossiite-(Ce)

Formula
CeAl2B4O10 
Crystal System
Hexagonal 
Cleavage
Perfect, None, None 
Luster
Vitreous (Glassy) 
Color
brownish yellow, light yellow, lemon 
Streak
white 
Class
Hexagonal - Ditrigonal Dipyramidal 
Hardness
2 
Collection
William & Anne Cook Collection
On Dakota Matrix
Previously Sold Peprossiite-(Ce)
On Dakota Matrix
Other Available Peprossiite-(Ce)
WebMineral
View Peprossiite-(Ce)
Mindat
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Sigloite - CL62658
Sigloite - CL62658

Sigloite

with Paravauxite - #CL62658
Locality
Siglo Veinte mine, Llallagua, Bolivia 
Formula
Fe3+Al2(PO4)2(OH)3·7H2O 
Availability
Available
Price
$125.00
Size
9 x 6.5 x 2 cm - Sm Cabinet 
Tagged
phosphate  
Special Info
Type Locality 

Two closely related rare phosphate minerals; Sigloite with a ferric (Fe III) ion phasing to Paravauxite with a ferrous (Fe II) ion. The Paravauxite are the white crystals and the Sigloite are the brown crystals. Very nice specimen from the hydrothermal tin veins of Llallagua.


Sigloite

Formula
Fe3+Al2(PO4)2(OH)3·7H2O 
Crystal System
Triclinic 
Crystal Habit
Pseudomorphous 
Cleavage
Perfect, Good, None 
Luster
Vitreous - Pearly 
Color
brown, light brown, light yellow, straw yellow 
Streak
white 
Class
Triclinic - Pinacoidal 
Hardness
3 
Collection
Chet S. Lemanski, Jr. Collection
Special Info
Type Locality
On Dakota Matrix
Previously Sold Sigloite
On Dakota Matrix
Other Available Sigloite
WebMineral
View Sigloite
Mindat
View Sigloite
Spencerite - BAC62632
Spencerite - BAC62632

Spencerite

#BAC62632
Locality
Hudson Bay mine, Salmo, British Columbia, Canada 
Formula
Zn4(PO4)2(OH)2·3H2O 
Availability
Available
Price
$225.00
Size
2.5 x 2.5 x 2 cm - Thumbnail 
Tagged
phosphate  
Special Info
Type Locality 

Spencerite is an extremely rare zinc phosphate found in only two deposits worldwide. Both deposits are carbonate hosted replacement deposits. It has not been found in a pegmatite deposit to-date, eventhough there are plenty of zinc phophates found in pegmatites. This specimen has very nice cleavable pearly plates in a large crystal aggregate. In-hand you can see the beautiful pearly flashes.


Spencerite

Formula
Zn4(PO4)2(OH)2·3H2O 
Crystal System
Monoclinic 
Crystal Habit
Radial 
Cleavage
Perfect, Imperfect, None 
Luster
Vitreous - Pearly 
Color
white 
Streak
white 
Class
Monoclinic - Prismatic 
Hardness
3 
Collection
William & Anne Cook Collection
Special Info
Type Locality
Mineralpedia
View Spencerite
On Dakota Matrix
Previously Sold Spencerite
On Dakota Matrix
Other Available Spencerite
WebMineral
View Spencerite
Mindat
View Spencerite
Valentinite - CL62653
Valentinite - CL62653

Valentinite

with Galena - #CL62653
Locality
San José mine, Oruro City, Oruro Dept., Bolivia 
Formula
Sb2O3 
Availability
Available
Price
$75.00
Size
4.5 x 4 x 2.5 cm - Miniature 

Large 1cm plus crystals of Valentinite with included and oriented crystals of tiny Galena crystals. The crystals flash when the specimen is rocked back and forth from the oriented crystals of Galena. The matrix is Pyrite.


Valentinite

Formula
Sb2O3 
Crystal System
Orthorhombic 
Crystal Habit
Euhedral Crystals, Divergent, Striated 
Cleavage
Perfect, Distinct, None 
Luster
Adamantine 
Color
brownish reddish, colorless, gray white, grayish, yellowish 
Streak
white 
Class
Orthorhombic - Dipyramidal 
Fracture
Uneven 
Hardness
2.5-3 
Collection
Chet S. Lemanski, Jr. Collection
Mineralpedia
View Valentinite
On Dakota Matrix
Previously Sold Valentinite
On Dakota Matrix
Other Available Valentinite
WebMineral
View Valentinite
Mindat
View Valentinite

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