Pyrite on Calcite from Chivor, Colombia – Pyritohedral Crystals

This Pyrite and Calcite specimen from the Chivor District in Colombia features numerous brass-yellow to golden Pyrite crystals positioned on and between white to colorless Calcite crystals. Several of the larger Pyrite crystals are distinctly pyritohedral and show sharply defined, strongly metallic crystal faces.

With dimensions of 9.3 × 8.8 × 4.8 cm and a weight of 382 g, this is a Cabinet specimen. The contrast between the bright Calcite and the metallic Pyrite gives the specimen a strong visual impact, while the three-dimensional arrangement of the crystals makes it interesting from several viewing angles.

Pyritohedral Pyrite crystals between Calcite

Several of the larger Pyrite crystals show a clearly pyritohedral crystal habit. Some sit freely on the Calcite, while others are partly embedded between the white to colorless crystals. A number of the Pyrite crystals are modified by additional faces, although the underlying pyritohedral form remains readily recognizable.

The Pyrite displays a strong metallic luster. Depending on the viewing angle, individual faces reflect the light intensely and stand out clearly against the light-colored Calcite matrix.

The Calcite itself is also well crystallized. Numerous larger white to colorless crystals form a three-dimensional matrix in which the Pyrite crystals occur at different levels and orientations.

Pyrite and Calcite from the Chivor District

The Chivor District in Boyacá belongs to Colombia’s eastern emerald belt. In addition to Emerald, the mineralized zones of the district also contain associated minerals such as Calcite and Pyrite. This specimen illustrates that mineral association particularly well, as the Pyrite crystals are directly intergrown with a distinctly crystallized Calcite matrix.

The combination of pyritohedral Pyrite crystals, metallic luster and white to colorless Calcite makes the specimen both mineralogically and visually interesting.

Read more about Chivor and the emerald regions of Colombia in my detailed article about Colombia’s emerald deposits.