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0 item @ $0.00  

Hollandite

#39289

Hollandite

#39289
Availability
Sold
Size
8 x 5 x 3 cm - Sm Cabinet 
Formula
BaMn2+Mn4+7O16 (RRUFF)
Locality
Deep Portland pit, Wharf mine, Lawrence Co., South Dakota, United States

Black needles in groups to 1mm on Quartz Monzonite matrix.

EDS Confirmed

Hollandite

Formula
BaMn2+Mn4+7O16 
Crystal System
Monoclinic 
Crystal Habit
Striated, Prismatic, Acicular 
Cleavage
Good, None, None 
Luster
Earthy (Dull) 
Color
grayish black, black, silver gray 
Streak
black 
Class
Monoclinic - Prismatic 
Fracture
Brittle 
Hardness
4-6 

Data courtesy of Webmineral.

Special Info
EDS Confirmed

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