Description

This specimen comes from the Huanzala Mine, a renowned mineral locality in South America, located in the province of Huallanca, Ancash region, Peru. The formation is an excellent representation of the classic association between calcite, sphalerite and pyrite, but stands out for the rare crystal morphology of calcite.
The calcite crystals exhibit a short prismatic habit with hexagonal terminations, developed tridimensionally and well distributed over the entire matrix. The color ranges from icy white to milky transparent, with light internal zoning visible under backlight. The faces are lustrous and perfectly developed, with a satin-like reflection.
The matrix is composed of a heterogeneous combination of lustrous black sphalerite (ZnS), golden pyrite and accessory galena crystals. The pyrite occurs in cubic and pentagon-dodecahedral forms.
Distinctive features:
Location: Huanzala Mine, Huallanca, Ancash, Peru
Calcite crystal system: Trigonal (hexagonal shape due to twinning and prismatic growth)
Minerals present: Calcite, Pyrite, Sphalerite, Galena (accessory), Quartz
Main crystal habit: Truncated hexagonal calcite, rare for this locality
Rarity: Uncommon crystal morphology, excellent aesthetics and mineral composition
Use: Display, museum collection, mineralogy
The hexagonal habit of calcite is significantly less common than the typical scalenohedral or rhombohedral forms found in the mine. This makes the specimen especially sought-after among collectors specialized in atypical crystallographies.