Calcite from Raigad, India – Yellow Pseudocubic Crystals on Basalt

This Calcite specimen from the Raigad District in Maharashtra, India features three larger, intergrown Calcite crystals on a dark basalt matrix. The pale yellow crystals show a striking blocky to pseudocubic appearance and stand out clearly against the white associated mineralization and dark host rock.

Measuring 6.8 × 4 × 4 cm and weighing 98.4 g, this is a small cabinet specimen. The three dominant Calcite crystals form a compact group and give the specimen a pronounced three-dimensional appearance despite its relatively modest size.

Pale yellow Calcite with an unusual habit

The Calcite crystals show a pale yellow to yellowish-cream coloration. Their habit is strongly blocky to pseudocubic in appearance, distinguishing them from the more common scalenohedral or rhombohedral forms of Calcite.

The crystals are closely intergrown, while their individual bounding faces remain clearly visible. Some crystal surfaces show a noticeable luster. Natural internal structures and minor irregularities can also be seen within the crystals.

The Calcite is predominantly translucent. The crystals do not appear clearly transparent.

Calcite on basalt from Maharashtra

The Raigad District in Maharashtra lies within the extensive basalt province of the Deccan Traps. Numerous secondary minerals formed in cavities and fractures within these basaltic rocks, including Calcite as well as various zeolite and apophyllite-group minerals.

On this specimen, the yellowish Calcite crystals occur together with a dense white associated mineralization on the dark basalt matrix. The white crystals are deliberately left unidentified because a reliable mineralogical determination cannot be made from the specimen and photographs alone.

Greenish coatings and mineralized areas are also visible locally along the contact between the basalt and the pale mineralization. These are likewise left unidentified without analytical confirmation.