Prehnite

Prehnite weighing 188 grams and measuring 110 x 70 x 40 mm, originating from South Africa. This incredible specimen delights us with its perfect crystallization in the form of tabular, ridge-like crystals.

Prehnite is a mineral belonging to the silicate group, specifically the phyllosilicate subgroup. It is a calcium aluminum aluminosilicate, although up to 7% of the aluminum may be replaced by iron.

It is a secondary mineral formed in the cracks of basic volcanic rocks, provided they are rich in calcium. It is also found in igneous rocks and, less frequently, as a product of low-grade metamorphism. In all these rock types, it can appear filling cavities as botryoidal or fan-shaped formations, or lining fractures. Well-defined crystals are rare and small.

Origin: South Africa

Dimensions: 110 x 70 x 40 mm

Weight: 188 grams