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0 item @ $0.00  

Phosphate Minerals

Friday, 26 August 2016 12:00 PM

Primary and Metasomatic phosphates are found mostly in pegmatites, but also occur in many sedimentary deposits. Most of these phosphates look the same. We will attempt to unlock the mystery of these unique minerals which can often contain secondary phosphate minerals. 

SOLD
Alluaudite - PD35933
Alluaudite - PD35933

Alluaudite

#PD35933
Locality
Pleasant Valley mine, Custer Co., South Dakota, United States 
Formula
(Na,Ca)2(Mn,Mg,Fe2+)(Fe3+,Mn2+)2(PO4)3 
Availability
Sold
Size
6 x 4 x 5 cm - Sm Cabinet 
Tagged
phosphate , pegmatite mineral  

Tough, compact, fine grained mineral, which usually does not yield secondary phosphates. 

Alluaudite is more of a metasomatic exchange product than it is a primary phase with lithium in parent triphyllite being replaced by Na and Ca, according to Paul Moore in Min. Record (1973). Alluaudite occurs in many pegmatites but may also occur in phosphorites. 


Alluaudite

Formula
(Na,Ca)2(Mn,Mg,Fe2+)(Fe3+,Mn2+)2(PO4)3 
Crystal System
Monoclinic 
Crystal Habit
Platy, Fibrous, Nodular 
Cleavage
Good, Good, None 
Color
brownish yellow, green, yellow, black 
Streak
brownish yellow 
Class
Monoclinic - Prismatic 
Hardness
5-5.5 
Collection
Phillips Collection

Alluaudite

#41597
Locality
Townsite mine, Custer Co., South Dakota, United States 
Formula
(Na,Ca)2(Mn,Mg,Fe2+)(Fe3+,Mn2+)2(PO4)3 
Availability
Sold
Size
7 x 5 x 3.5 cm - Sm Cabinet 
Tagged
phosphate , pegmatite mineral  
Special Info
XRD Confirmed 
Special Info
Raman 

Solid dark green granular mass. This is a tightly packed mass which is very hard to break. Paul Moore classifies this mineral as an metasomatic product of parent Triphylite with the addition of Na and Ca. 


Alluaudite

Formula
(Na,Ca)2(Mn,Mg,Fe2+)(Fe3+,Mn2+)2(PO4)3 
Crystal System
Monoclinic 
Crystal Habit
Platy, Fibrous, Nodular 
Cleavage
Good, Good, None 
Color
brownish yellow, green, yellow, black 
Streak
brownish yellow 
Class
Monoclinic - Prismatic 
Hardness
5-5.5 
Special Info
XRD Confirmed
Special Info
Raman
SOLD
Alluaudite - 41598
Alluaudite - 41598

Alluaudite

#41598
Locality
Lofton mine, Custer Co., South Dakota, United States 
Formula
(Na,Ca)2(Mn,Mg,Fe2+)(Fe3+,Mn2+)2(PO4)3 
Availability
Sold
Size
6 x 5.5 x 3.5 cm - Sm Cabinet 
Tagged
phosphate , pegmatite mineral  
Special Info
XRD Confirmed 
Special Info
Raman 

Tough hard dark green granular mass. 


Alluaudite

Formula
(Na,Ca)2(Mn,Mg,Fe2+)(Fe3+,Mn2+)2(PO4)3 
Crystal System
Monoclinic 
Crystal Habit
Platy, Fibrous, Nodular 
Cleavage
Good, Good, None 
Color
brownish yellow, green, yellow, black 
Streak
brownish yellow 
Class
Monoclinic - Prismatic 
Hardness
5-5.5 
Special Info
XRD Confirmed
Special Info
Raman

Alluaudite

with Strengite - #45181
Locality
Buranga pegmatite, Gatumba dist., Western Prov., Rawanda 
Formula
(Na,Ca)2(Mn,Mg,Fe2+)(Fe3+,Mn2+)2(PO4)3 
Availability
Sold
Size
9 x 6 x 6 cm - Sm Cabinet 
Tagged
phosphate , pegmatite mineral  

A good-sized chunk of blackish Alluaudite partially altered to Strengite.


Alluaudite

Formula
(Na,Ca)2(Mn,Mg,Fe2+)(Fe3+,Mn2+)2(PO4)3 
Crystal System
Monoclinic 
Crystal Habit
Platy, Fibrous, Nodular 
Cleavage
Good, Good, None 
Color
brownish yellow, green, yellow, black 
Streak
brownish yellow 
Class
Monoclinic - Prismatic 
Hardness
5-5.5 
SOLD
Amblygonite - 41606
Amblygonite - 41606

Amblygonite

- Montebrasite - #41606
Locality
Tin Mountain mine, Custer Co., South Dakota, United States 
Formula
LiAlPO4
Availability
Sold
Size
7 x 4.5 x 5 cm - Sm Cabinet 
Tagged
phosphate , pegmatite mineral  

Solid white mass of undetermined Amlygonite-Montebrasite series. 


Amblygonite

Formula
LiAlPO4
Crystal System
Triclinic 
Crystal Habit
Columnar, Euhedral Crystals, Prismatic 
Cleavage
Perfect, Good, Distinct 
Luster
Vitreous - Pearly 
Color
white, yellow, gray, bluish gray, greenish gray 
Streak
white 
Class
Triclinic - Pinacoidal 
Fracture
Uneven 
Hardness
5.5-6 
SOLD
Amblygonite - 45179
Amblygonite - 45179

Amblygonite

- Montebrasite - #45179
Locality
Mount Rubellite Quarries, Hebron, Oxford Co., Maine, United States 
Formula
LiAlPO4
Availability
Sold
Size
6.5 x 5 x 3 cm - Sm Cabinet 
Tagged
phosphate , pegmatite mineral  

White mass of Amblygonite.


Amblygonite

Formula
LiAlPO4
Crystal System
Triclinic 
Crystal Habit
Columnar, Euhedral Crystals, Prismatic 
Cleavage
Perfect, Good, Distinct 
Luster
Vitreous - Pearly 
Color
white, yellow, gray, bluish gray, greenish gray 
Streak
white 
Class
Triclinic - Pinacoidal 
Fracture
Uneven 
Hardness
5.5-6 

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