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0 item @ $0.00  

Englishite Montgomeryite

#18355

Englishite Montgomeryite

#18355
Availability
Sold
Size
6 x 3 x 2.5 cm - Sm Cabinet 
Formula
K3Na2Ca10Al15(OH)7(PO4)21·26H2O (RRUFF)
Locality
Tip Top mine, Custer Co., South Dakota, United States
Tagged
phosphate , pegmatite mineral

Nice combination of Englishite and Montgomeryite. The Englishite is hard to see in the photos, since there is also Whitlockite and white Microcline. With a scope though you'll see little cottonball-like spherulites of Englishite. The red is of course Montgomeryite.

Englishite

Formula
K3Na2Ca10Al15(OH)7(PO4)21·26H2
Crystal System
Monoclinic 
Crystal Habit
Micaceous, Aggregates, Friable 
Cleavage
Perfect, None, None 
Luster
Vitreous - Pearly 
Color
colorless, white 
Streak
white 
Class
Monoclinic - Sphenoidal 
Hardness

Data courtesy of Webmineral.

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