Pyrophanite

Field of view: 3 mm. Pyrophanite associated with rhodonite. The tabular black crystal and surrounding black grains are pyrophanite. The face with a submetallic luster at the center is (001) cleavage face parallel to the basal plane. The surrounding massive host composed of fine pale pink grains is rhodonite.

Recovered from a chert-hosted bedded manganese deposit subjected to Hornblende-hornfels facies contact metamorphism by S-type (Ilmenite-series) granodiorite.