3N62: Group of Calcite crystals, one of them clearly dominant. Faces and edges are very sharp and clearly show two twinned scalenohedra on one of the crystals. A curiosity from a mine very famous for its Fluorites.
Coroña Shaft, Josefa-Veneros Norte vein, La Collada mining area, zona minera de La Collada, Siero, Comarca Oviedo, Principality of Asturias (Asturias)  Spain (1980)

Specimen size: 8.1 × 8.0 × 3.5 cm = 3.19” × 3.15” × 1.38”

Main crystal size: 6.0 × 8.0 cm = 2.36” × 3.15”