This elongated calcite crystal comes from the deposits of optical calcite of José María Patoni. These mining works are famous worldwide for the purity, transparence and crystallographic complexity of its calcite crystals. These specimens were formed by mineral rich hydrothermal fluids flowing through rhyolitic pyroclastic materials, where they found faults and fissures, a perfect place to grow.
This specimen shows faces of the prism, both scalenohedrons and rhombohedrons (positive and negative), echeloned faces and a marked apical pinacoid. Excellent transparence and brilliance. With a minor matrix. A worlwide classic for calcite and crystallography.