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Montgomeryite & Robertsite

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BCK652760

Montgomeryite & Robertsite

Kay Robertson collection
Classic Locality

Description Tabs

Description
Locality: 
Tip Top Mine, Fourmile, Custer County, South Dakota, United States of America
Class: 
Crystals on Matrix
Size Range: 
Thumbnail (1-3cm)
Size: 
2 × 0.8 × 1 cm
Description

You are bidding on a small sample with very nice blades of red montgomeryite on matrix with clusters of brown robertsite crystals on a bed of bobdownsite. Kay Robertson collection. 

Mineral Data
What's on the rock

Montgomeryite

Formula: 
Ca4MgAl4(PO4)6(OH)4·12H2O
Strunz: 
8.DH.25
Hardness: 
4.0
Type Locality: 
Clay Canyon, Fairfield, Oquirrh Mts, Utah Co., Utah, USA

Robertsite

Formula: 
Ca3Mn3+4(PO4)3O2·3H2O
Strunz: 
8.DH.30
Hardness: 
3.5
Streak: 
Red-brown
Type Locality: 
Tip Top Mine (Tip Top pegmatite), Fourmile, Custer District, Custer Co., South Dakota, USA

Seller Information

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