Scolecite with Stilbite & Apophyllite

Scolecite with Stilbite and Apophyllite from Ahmednagar, Maharashtra, India, measuring 76 × 48 × 25 mm and weighing 45 grams. A good example of the kind of multi-species zeolite assemblage Maharashtra's basalt quarries are known for.

Scolecite is a fibrous calcium zeolite, closely related to Natrolite and Mesolite, and it typically forms as sprays of fine, silky, radiating needles. The Deccan Traps, an enormous pile of flood basalts erupted around 66 million years ago across much of western India, have gas cavities that have produced some of the world's finest zeolite specimens, with Scolecite, Stilbite and Apophyllite all forming from the same family of late-stage, low-temperature mineralising fluids moving through the cooling lava, which is why the three so often turn up together in the one cavity.

A piece showing all three species together is a good teaching specimen for the range of forms a single mineralising episode can produce, and it is a genuinely attractive one as well. This piece carries a double provenance, the David Vince Collection and Crystal Habit.