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Babingtonite
Chemical Formula	Ca2(Fe,Mn)FeSi5O14(OH)
Species	Silicates
Crystal System	Triclinic
Mohs Scale	5-6
Specific Gravity	3.3
Color	Dark green to black
Luster	Vitreous
Refractive Index	n = 1.700 n = 1.710 n = 1.725
Diaphaneity	Opaque
Cleavage	PerfectPerfect on Good on and
Fracture	Irregular/Uneven
Crystal Habit：Prismatic crystals
Geological Setting：Veins cutting granitic pegmatites and diorites, cavities and vugs in mafic volcanic rocks and gneisses, skarns.

Babingtonite is a calcium iron manganese inosilicate mineral with the formula Ca₂(Fe,Mn)FeSi₅O₁₄(OH). It is unusual in that iron(III) completely replaces the aluminium so typical of silicate minerals. It is a very dark green to black translucent (in thin crystals or splinters) mineral crystallizing in the triclinic system with typically radial short prismatic clusters and druzy coatings. It occurs with zeolite minerals in cavities in volcanic rocks. Babingtonite contains both iron(II) and iron(III) and shows weak magnetism. It has a Mohs hardness of 5.5 to 6 and a specific gravity of 3.3.

It was first described in 1824 from samples from Arendal, Aust-Agder, Norway (which is its type locality) and was named after the Irish physician and mineralogist William Babington (1757–1833).

It is the official mineral (mineral emblem) of the Commonwealth of Massachusetts.