Helvine

Field of view: 5 mm. Helvine associated with quartz and rhodonite. The yellowish-green triangles are cross sections of tetragonal helvine. Helvite veins less than 10 mm thickness have been reported in chert from this locality.

Recovered from a chert-hosted bedded manganese deposit subjected to Hornblende-hornfels facies contact metamorphism by S-type (Ilmenite-series) granodiorite. Formed in the Late Cretaceous (83 Ma).

Helvine from this location was described in 1960.