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1 item @ $125.00  

Montgomeryite with Robertsite

#45625

Montgomeryite with Robertsite

#45625
Availability
Sold
Size
3.5 x 3 x 2.5 cm - Miniature 
Formula
Ca4MgAl4(PO4)6(OH)4·12H2O (RRUFF)
Locality
Tip Top mine, Custer Co., South Dakota, United States
Tagged
phosphate , pegmatite mineral

Deep red bladed Montgomeryite crystals to 0.5mm and less. Montgomeryite from the Tip Top mine is the best in the world. I have not seen red Montgomeryite anywhere else. Associated is black, good crystals of Robertsite. It may actually be deep red.

Montgomeryite

Formula
Ca4MgAl4(PO4)6(OH)4·12H2
Crystal System
Monoclinic 
Cleavage
Perfect, Indistinct, None 
Luster
Vitreous (Glassy) 
Color
colorless, yellowish, white, green, red 
Streak
white 
Class
Monoclinic - Prismatic 
Hardness

Data courtesy of Webmineral.

Collection
Chris van Laer Collection

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