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0 item @ $0.00  

Mixed Minerals

Sunday, 21 February 2021 06:00 PM

Introducing the "Mixed Minerals" gallery which is part of our New Additions galleries. This gallery contains mineral specimens for sale including gillardite, grossular, ixiolite, krauskopfite, macdonaldite, and maskelynite and more from places like Carr Boyd Nickel Deposit, Western Austrialia, Australia, Sierra de Cruces, Coahuila, Mexico, Helen Beryl mine, Custer Co., South Dakota, United States, Esquire #1 claim, Fresno Co., California, United States, Big Creek, Fresno Co., California, United States, and Manicouagan Crater, Mont de Bablel, Quebec, Canada.

Gillardite

#55198
Locality
Carr Boyd Nickel Deposit, Western Austrialia, Australia 
Formula
Cu2+3NiCl2(OH)6 
Availability
Sold
Size
6 x 5 x 4 cm - Sm Cabinet 
Tagged
copper , nickel  
Special Info
Raman 

Raman verified Gillardite. The crystals are emerald to dak green rhombic-looking crystals to 0.75mm across face. Very good coverage. It's a good specimen, don't pass it up.


Gillardite

Formula
Cu2+3NiCl2(OH)6 
Crystal System
Trigonal 
Crystal Habit
Triangular Crystals, Aggregates 
Cleavage
Good, None, None 
Luster
Vitreous (Glassy) 
Color
dark green 
Streak
green 
Class
Trigonal - Rhombohedral 
Fracture
Splintery 
Hardness
Special Info
Raman

Grossular

garnet - #55195
Locality
Sierra de Cruces, Coahuila, Mexico 
Formula
Ca3Al2(SiO4)3 
Availability
Sold
Size
4.5 x 4.5 x 4 cm - Miniature 

A beautiful nicely formed Grossular crystal to 1.5cm with several much smaller crystals in rhyolite matrix. A great specimen, well-trimmed, suitable for a cotten-lined box or an eye-catching display piece.


Grossular

SOLD
Ixiolite - 55159
Ixiolite - 55159

Ixiolite

#55159
Locality
Helen Beryl mine, Custer Co., South Dakota, United States 
Formula
(Ta,Nb,Sn,Fe,Mn)O2 
Availability
Sold
Size
6 x 5 x 2.5 cm - Sm Cabinet 
Tagged
tin  
Special Info
EDS Confirmed 

(EDS) It looks like Columbite but contains enough manganese, iron, and tin to be called Ixiolite, which is rare in the Black Hills. This is so far the only locality in the Black Hills. Streak alone is not enough to distingish it from Columbite but can eliminate Cassiterite, which is usually colorless to very hard brownish red. This specimen streaks a hard black. Of course nothing is concrete with any of these black oxides in pegmatites so EDS is pretty much required. 


Ixiolite

Formula
(Ta,Mn,Nb)O2 
Crystal System
Monoclinic 
Crystal Habit
Prismatic, Irregular Grains 
Cleavage
Indistinct, None, None 
Luster
Metallic 
Color
gray, black, steel gray 
Streak
dark brown 
Class
Monoclinic - Prismatic 
Fracture
Conchoidal - Uneven 
Hardness
6-6.5 
Special Info
EDS Confirmed
On Dakota Matrix
Previously Sold Ixiolite
On Dakota Matrix
Other Available Ixiolite
WebMineral
View Ixiolite
Mindat
View Ixiolite

Krauskopfite

#42759
Locality
Esquire #1 claim, Fresno Co., California, United States 
Formula
BaSi2O5·3H2
Availability
Sold
Size
3.5 x 2 x 2 cm - Miniature 
Special Info
Type Locality 

Extremely rare barium silicate occuring as an alteration product of Sanbornite. The Krauskopfite can be seen as colorless, very reflective, cleavages to 4mm on the face of the specimen.


Krauskopfite

Formula
BaSi2O5·3H2
Crystal System
Monoclinic 
Crystal Habit
Prismatic 
Cleavage
Perfect, Perfect, None 
Luster
Vitreous - Pearly 
Color
colorless, white 
Streak
white 
Class
Monoclinic - Prismatic 
Hardness
Special Info
Type Locality

Macdonaldite

#PD42276
Locality
Big Creek, Fresno Co., California, United States 
Formula
BaCa4Si16O36(OH)2·10H2
Availability
Sold
Size
3 x 1.5 x 1 cm - Thumbnail 
Special Info
Type Locality 

Slender, acicular colorless crystals to around 1mm. Very rare. Minor Gillespite (red) in matrix on backside.


Macdonaldite

Formula
BaCa4Si16O36(OH)2·10H2
Crystal System
Orthorhombic 
Crystal Habit
Acicular 
Cleavage
Perfect, Good, Indistinct 
Luster
Vitreous - Silky 
Color
colorless, white 
Streak
white 
Class
Orthorhombic - Dipyramidal 
Hardness
3.5-4 
Collection
Don Phillips Collection
Special Info
Type Locality

Maskelynite

#54988
Locality
Manicouagan Crater, Mont de Bablel, Quebec, Canada 
Availability
Available
Price
$60.00
Size
6 x 4 x 1 cm - Sm Cabinet 

Not an IMA approved mineral as it is actually a fused product of a meteorite fall. It is essentially a glassy pseudomorph after plagioclase. A document can be found in the American Mineralogist Jan-Feb V52.


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