Outstanding dark green microcrystals of the extremely rare Zn-Fe arsenate mineral mapìmite from the TL in Ojuela mine, Mexico on the typical brown matrix of the Ojuela specimens. — Photo: David Hospital · CC BY 4.0
Mapimite
Mapimite is an IMA-recognized mineral species in the arsenate class, with the chemical formula Zn₂Fe³⁺₃(AsO₄)₃(OH)₄·10H₂O.
It crystallizes in the monoclinic crystal system (space group Cm).
Key properties: Mohs hardness 3; specific gravity 2.95; Vitreous luster; optically biaxial.
IMA symbol Mpm, IMA status: approved, named in 1978.
A rare secondary mineral found in the oxidized zone of an arsenic-rich hydrothermal polymetallic ore deposit.
It is found associated with Scorodite, adamite, smithsonite, “limonite”.
The name refers to the Mapimı́ mining district in Mexico that produced the first specimens.