Akrochordite
Appearance
Akrochordite | |
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![]() Bright green, vitreous, cluster of eveite (under 0.5 mm) and brown, subhedral akrochordite in a contrasting, pink, granular carbonate matrix | |
General | |
Category | Phosphate minerals |
Formula (repeating unit) | (Mn,Mg)4(AsO4)2(OH)4.4H2O |
Strunz classification | 8.DD.10 |
Crystal system | Monoclinic |
Crystal class | Prismatic (2/m) (same H-M symbol) |
Space group | P21/c |
Identification | |
Color | Yellowish red-brown, pale to dark brown, pale pink |
Cleavage | Perfect. On {010} , perfect; a second, perpendicular to the first. |
Tenacity | Brittle |
Mohs scale hardness | 3+1⁄2 |
Luster | Sub-Vitreous, resinous, dull |
Diaphaneity | Translucent |
References | [1][2][3] |
Akrochordite is an exceptionally rare hydrated hydrous arsenate mineral of the formula (Mn,Mg)4(AsO4)2(OH)4.4H2O and represents a small group of rare in the nature manganese (Mn) arsenates and, similarly to most other Mn-bearing arsenates, possess pinkish colour. It is typically associated with metamorphic Mn deposits.[2][4]