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Alleghanyite
Chemical Formula	Mn5(SiO4)2(OH)2
Species	Silicates
Crystal System	Monoclinic
Mohs Scale	5
Specific Gravity	4-4.11
Color	Brown, bright pink, grayish pink, white
Luster	Vitreous, Dull
Refractive Index	n = 1.756 n = 1.780 n = 1.792
Diaphaneity	Transparent, Translucent
Cleavage	None
Fracture	Conchoidal
Crystal Habit：Granular; anhedral to subhedral crystals in matrix
Geological Setting：in veins crosscutting franklinite ore near pegmatites in a metamorphosed stratiform Zn-Mn deposit

Alleghanyite is a moderately rare humite mineral with formula Mn₅(SiO₄)₂(OH)₂, belonging to the nesosilicates class. In general its occurrences are related with metamorphic (metamorphosed) manganese deposits. The mineral is named after Alleghany County, North Carolina, USA.