Calcite
Sennin, Waga village, Kitakami city, Iwate pref., Japan
Source for Quick lime and Sodium cyanide
Field of view: 20 mm. Calcite in an open space of the hedenbergite skarn. The granular white to transparent crystals are calcite. The opaque white parts at the center of each crystal are cores, and transparent scalenohedral crystals grow to the both sides. The light gray host is hedenbergite altered to actinolite.
Recovered from an open space of an oxidative metazomatic zone combined with skarn formed by contact metamorphism of S-type (Ilmenite-series) granodiorite. Formed in the middle Miocene (15 Ma).
Calcite from this location was described in 1900.
Other localities
- Chichibu Mine (Hydrothermal Skarn, Scalenohedral)
- Horado Mine (Hydrothermal Skarn, Granular)
- Nakatatsu Mine (Hydrothermal Skarn, Rhombohedral)
- Waga-Sennin Mine (Metasomatic Skarn, Scalenohedral)
- Choshi (Andesite, Granular)
- Kodomari (Hydrothermal, Scalenohedral)
- Shobusawa (Au-Ag vein, Scalenohedral)
- Mount Futago (Limestone, Rhombohedral)
- Koma (Calcareous sandstone, Twin)
- Cotswolds (Oolitic limestone, Granular)
- Iwakake (PrP facies, Scalenohedral)