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Southeast US Phosphates

Thursday, 23 April 2020 08:00 PM

Introducing the "Southeast US Phosphates" gallery which is part of our Special Edition galleries. This gallery contains mineral specimens for sale including straczekite, strengite and more from places like Union Carbide mine, Wilson Springs, Garland Co., Arkansas, United States, Three Oaks Gap, Polk Co., Arkansas, United States.

Straczekite

#DO53042
Locality
Union Carbide mine, Wilson Springs, Garland Co., Arkansas, United States 
Formula
(Ca,K,Ba)V8O20·3H2
Availability
Sold
Size
5 x 4 x 3 cm - Miniature 
Tagged
vanadium  

No, this is not a phosphate! Sorry. Straczekite is a rare black mineral with vanadium and these are exceptional crystals. They are platy and occur in curled-up groups to around 1mm.


Straczekite

Formula
(Ca,K,Ba)V8O20·3H2
Crystal System
Monoclinic 
Crystal Habit
Microscopic Crystals, Fibrous 
Cleavage
Perfect, None, None 
Luster
Greasy (Oily) 
Color
greenish black 
Streak
greenish black 
Class
Monoclinic - Prismatic 
Hardness
1-2 
Collection
Don Owens Collection

Strengite

with Kidwellite - #BN53052
Locality
Three Oaks Gap, Polk Co., Arkansas, United States 
Formula
Fe3+PO4·2H2
Availability
Sold
Size
6 x 4.5 x 3.5 cm - Sm Cabinet 
Tagged
phosphate  

The Kidwellite from Three Oaks is perhaps the best around. The digital camera unfortunately washes out the green. The first photo (and this goes with the rest of the specimens in this website update) shows the true color best. It is a lime green of sorts and is a microcrystalline crusts which covers a layer of deep red Beraunite, which is shown in the last two photos. Upon the Kidwellite are at least a dozen Strengite spheres. These are a nice sparkly purple and measure up to about 1.5mm.

These are no longer available. They came from the Dr. Buford Nichols collection who collected them along with Dr. Albert Kidwell himself. According to the late, great Art Smith in his book "Collecting Arkansas Minerals" the locality is collected out and obliterated. It requires a four-wheel drive to get there. 


Strengite

Formula
Fe3+PO4·2H2
Crystal System
Orthorhombic 
Crystal Habit
Spherical, Radial, Botryoidal 
Cleavage
Good, Poor, None 
Luster
Vitreous (Glassy) 
Color
colorless, pale violet, deep violet, red, carmine red 
Streak
white 
Class
Orthorhombic - Dipyramidal 
Fracture
Brittle - Conchoidal 
Hardness
3.5 
Collection
Dr. Buford Nichols Collection
Mineralpedia
View Strengite
On Dakota Matrix
Previously Sold Strengite
On Dakota Matrix
Other Available Strengite
WebMineral
View Strengite
Mindat
View Strengite

Strengite

with Cacoxenite on Beraunite - #BN53056
Locality
Three Oaks Gap, Polk Co., Arkansas, United States 
Formula
Fe3+PO4·2H2
Availability
Sold
Size
6 x 4.5 x 2 cm - Sm Cabinet 
Tagged
phosphate  

Lime green globular Kidwellite on red Beraunite. Upn the Kidwellite are 2mm purple crystal groups of Strengite. Excellent specimen.


Strengite

Formula
Fe3+PO4·2H2
Crystal System
Orthorhombic 
Crystal Habit
Spherical, Radial, Botryoidal 
Cleavage
Good, Poor, None 
Luster
Vitreous (Glassy) 
Color
colorless, pale violet, deep violet, red, carmine red 
Streak
white 
Class
Orthorhombic - Dipyramidal 
Fracture
Brittle - Conchoidal 
Hardness
3.5 
Collection
Dr. Buford Nichols Collection
Mineralpedia
View Strengite
On Dakota Matrix
Previously Sold Strengite
On Dakota Matrix
Other Available Strengite
WebMineral
View Strengite
Mindat
View Strengite

Strengite

with Kidwellite on Beraunite - #BN53057
Locality
Three Oaks Gap, Polk Co., Arkansas, United States 
Formula
Fe3+PO4·2H2
Availability
Sold
Size
7 x 4 x 3 cm - Sm Cabinet 
Tagged
phosphate  

This one is special. On the right side are numerous Strengite crystal groups to 2mm on golden yellow, fibrous Cacoxenite. I have not seen this combination before. Usually the Strengite sits directly upon the Kidwellite. The Kidwellite is a nice darker green and as usual has a globular habit. There is also excellent deep red and bladed Beraunite on the sides.


Strengite

Formula
Fe3+PO4·2H2
Crystal System
Orthorhombic 
Crystal Habit
Spherical, Radial, Botryoidal 
Cleavage
Good, Poor, None 
Luster
Vitreous (Glassy) 
Color
colorless, pale violet, deep violet, red, carmine red 
Streak
white 
Class
Orthorhombic - Dipyramidal 
Fracture
Brittle - Conchoidal 
Hardness
3.5 
Collection
Dr. Buford Nichols Collection
Mineralpedia
View Strengite
On Dakota Matrix
Previously Sold Strengite
On Dakota Matrix
Other Available Strengite
WebMineral
View Strengite
Mindat
View Strengite

Strengite

with Kidwellite on Beraunite - #BN53058
Locality
Three Oaks Gap, Polk Co., Arkansas, United States 
Formula
Fe3+PO4·2H2
Availability
Sold
Size
4.5 x 4 x 1.5 cm - Miniature 
Tagged
phosphate  

Miniature size specimen of globular, lime green Kidwellite with several sparkly purple hemispherical groups of Strengite to 2mm. The color of the actual specimen in-hand is a much better brighter green.


Strengite

Formula
Fe3+PO4·2H2
Crystal System
Orthorhombic 
Crystal Habit
Spherical, Radial, Botryoidal 
Cleavage
Good, Poor, None 
Luster
Vitreous (Glassy) 
Color
colorless, pale violet, deep violet, red, carmine red 
Streak
white 
Class
Orthorhombic - Dipyramidal 
Fracture
Brittle - Conchoidal 
Hardness
3.5 
Collection
Dr. Buford Nichols Collection
Mineralpedia
View Strengite
On Dakota Matrix
Previously Sold Strengite
On Dakota Matrix
Other Available Strengite
WebMineral
View Strengite
Mindat
View Strengite

Strengite

with Cacoxenite on Beraunite - #BN53059
Locality
Three Oaks Gap, Polk Co., Arkansas, United States 
Formula
Fe3+PO4·2H2
Availability
Sold
Size
3.5 x 2 x 2 cm - Miniature 
Tagged
phosphate  

Eye-catching specimen. It is a thumnail sized specimen with an incredible nest of purple Strengite balls to 1mm sitting upon golden fibrous Cacoxenite with a little Kidwellite. Around the sides you can see a layer of dark red Beraunite.


Strengite

Formula
Fe3+PO4·2H2
Crystal System
Orthorhombic 
Crystal Habit
Spherical, Radial, Botryoidal 
Cleavage
Good, Poor, None 
Luster
Vitreous (Glassy) 
Color
colorless, pale violet, deep violet, red, carmine red 
Streak
white 
Class
Orthorhombic - Dipyramidal 
Fracture
Brittle - Conchoidal 
Hardness
3.5 
Collection
Dr. Buford Nichols Collection
Mineralpedia
View Strengite
On Dakota Matrix
Previously Sold Strengite
On Dakota Matrix
Other Available Strengite
WebMineral
View Strengite
Mindat
View Strengite

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