Franklinite - ZnFe³⁺₂O₄

Habit: Crystallizes as black to reddish-brown octahedrons, commonly with rounded edges, also as granular and massive. Opaque, translucent in fine fragments, Metallic to semiMetallic, may be dull. Slightly magnetic.

Environment: Occurs in beds and veins formed by high-temperature metamorphism of marine carbonate sediments, and as a minor mineral in some manganese and iron deposits.

Etymology: Named for the locality and for Benjamin Franklin (1706-1790) after whom the town was named.