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Recently Released Special Editions

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 kidwellite, phosphosiderite, straczekite and more from places like York mine, Polk Co., Arkansas, United States, Three Oaks Gap, Polk Co., Arkansas, United States, Williams prospect, Coosa Co., Alabama, United States, Union Carbide mine, Wilson Springs, Garland Co., Arkansas, United States.

SOLD
Kidwellite - BN53053
Kidwellite - BN53053

Kidwellite

with Beraunite - #BN53053
Locality
York mine, Polk Co., Arkansas, United States 
Formula
NaFe3+9(PO4)6(OH)11·3H2O 
Availability
Sold
Size
4.5 x 2.5 x 2.5 cm - Miniature 
Tagged
phosphate  

This is a little gem of a specimen showing the cross-sections of Kidwellite spheres. The sections are 1mm across and are concentrically zoned in color and probably composition. You would need to scan these with an EDS to determine the chemical phases and would probably turn up Dufrenite and Rockbridgeite. The Beraunite is on the sides of the specimen as embedded dark red blades.


Kidwellite

Formula
NaFe3+9(PO4)6(OH)11·3H2O 
Crystal System
Monoclinic 
Crystal Habit
Fibrous, Columnar 
Cleavage
Perfect, None, None 
Luster
Silky 
Color
greenish yellow, greenish white, yellow, light green 
Streak
yellow 
Class
Monoclinic - Prismatic 
Hardness
3 
Collection
Dr. Buford Nichols Collection
Mineralpedia
View Kidwellite
On Dakota Matrix
Previously Sold Kidwellite
On Dakota Matrix
Other Available Kidwellite
WebMineral
View Kidwellite
Mindat
View Kidwellite
SOLD
Kidwellite - BN53055
Kidwellite - BN53055

Kidwellite

with Beraunite & Rockbridgeite - #BN53055
Locality
Three Oaks Gap, Polk Co., Arkansas, United States 
Formula
NaFe3+9(PO4)6(OH)11·3H2O 
Availability
Sold
Size
5 x 3.5 x 3.5 cm - Miniature 
Tagged
phosphate  

Globular light green Kidwellite on black, beady-looking and stalatitic Rockbridgeite(?). Amongst all of this are spherical groups of purple Strengite, much of which do not appear in the photos. Along the edges is a perimeter of deep red, bladed Beraunite (or Eleonorite). 


Kidwellite

Formula
NaFe3+9(PO4)6(OH)11·3H2O 
Crystal System
Monoclinic 
Crystal Habit
Fibrous, Columnar 
Cleavage
Perfect, None, None 
Luster
Silky 
Color
greenish yellow, greenish white, yellow, light green 
Streak
yellow 
Class
Monoclinic - Prismatic 
Hardness
3 
Collection
Dr. Buford Nichols Collection
Mineralpedia
View Kidwellite
On Dakota Matrix
Previously Sold Kidwellite
On Dakota Matrix
Other Available Kidwellite
WebMineral
View Kidwellite
Mindat
View Kidwellite
SOLD
Phosphosiderite - BN53063
Phosphosiderite - BN53063

Phosphosiderite

with Rockbridgeite & Beraunite - #BN53063
Locality
Williams prospect, Coosa Co., Alabama, United States 
Formula
Fe3+PO4·2H2O 
Availability
Sold
Size
5 x 3 x 3.5 cm - Miniature 
Tagged
phosphate  

Purple spherulites in cavities of phosphate pods mostly composed of Rockbridgeite and Beraunite.


Phosphosiderite

Formula
Fe3+PO4·2H2O 
Crystal System
Monoclinic 
Crystal Habit
Encrustations, Spherical 
Cleavage
Perfect, Distinct, None 
Luster
Vitreous (Glassy) 
Color
colorless, purple, pink, red, red violet 
Streak
white 
Class
Monoclinic - Prismatic 
Fracture
Uneven 
Hardness
3.5-4 
Collection
Dr. Buford Nichols Collection
Mineralpedia
View Phosphosiderite
On Dakota Matrix
Previously Sold Phosphosiderite
On Dakota Matrix
Other Available Phosphosiderite
WebMineral
View Phosphosiderite
Mindat
View Phosphosiderite
SOLD
Phosphosiderite - BN53066
Phosphosiderite - BN53066

Phosphosiderite

with Rockbridgeite - #BN53066
Locality
Williams prospect, Coosa Co., Alabama, United States 
Formula
Fe3+PO4·2H2O 
Availability
Sold
Size
5 x 2.5 x 3 cm - Miniature 
Tagged
phosphate  

Beaded Phosphosiderite less than 1mm in a grape-like bunches. Colorful.


Phosphosiderite

Formula
Fe3+PO4·2H2O 
Crystal System
Monoclinic 
Crystal Habit
Encrustations, Spherical 
Cleavage
Perfect, Distinct, None 
Luster
Vitreous (Glassy) 
Color
colorless, purple, pink, red, red violet 
Streak
white 
Class
Monoclinic - Prismatic 
Fracture
Uneven 
Hardness
3.5-4 
Collection
Dr. Buford Nichols Collection
Mineralpedia
View Phosphosiderite
On Dakota Matrix
Previously Sold Phosphosiderite
On Dakota Matrix
Other Available Phosphosiderite
WebMineral
View Phosphosiderite
Mindat
View Phosphosiderite
SOLD
Straczekite - DO53041
Straczekite - DO53041

Straczekite

#DO53041
Locality
Union Carbide mine, Wilson Springs, Garland Co., Arkansas, United States 
Formula
(Ca,K,Ba)V8O20·3H2O 
Availability
Sold
Size
4 x 3.5 x 2 cm - Miniature 
Tagged
vanadium  

Not a phosphate, but for sake of semi-completeness, it is here on this update because it is a good, rare mineral. Straczekite is tar black and crystallizes in plates grouped in curled-up balls. They are quite weird looking actually. You can't find them anywhere else. It's a four-locality mineral.


Straczekite

Formula
(Ca,K,Ba)V8O20·3H2O 
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
Mineralpedia
View Straczekite
On Dakota Matrix
Previously Sold Straczekite
On Dakota Matrix
Other Available Straczekite
WebMineral
View Straczekite
Mindat
View Straczekite
SOLD
Straczekite - DO53042
Straczekite - DO53042

Straczekite

#DO53042
Locality
Union Carbide mine, Wilson Springs, Garland Co., Arkansas, United States 
Formula
(Ca,K,Ba)V8O20·3H2O 
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)V8O20·3H2O 
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
Mineralpedia
View Straczekite
On Dakota Matrix
Previously Sold Straczekite
On Dakota Matrix
Other Available Straczekite
WebMineral
View Straczekite
Mindat
View Straczekite

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