Maharashtra Deccan Traprock Zeolites

History · Geology

About Maharashtra Deccan Traprock Zeolites

The Deccan flood basalts of Maharashtra, India — particularly the quarries near Pune (Poona), Nashik, Aurangabad, Jalgaon and Mumbai — are the world’s most prolific zeolite-producing locality. Active basalt quarrying since the 1980s has produced an enormous quantity of gem-grade zeolite specimens that defined the modern Asian and global zeolite collector market.

Geology

The host rocks are Late Cretaceous-Paleogene flood basalts of the Deccan Traps (~65 Ma), erupted as massive sheet flows. Late-stage hydrothermal fluids percolated through cooled basalt and crystallized zeolites in vesicles and amygdules. The vast volume and accessibility of the basalt quarries have made it the world’s zeolite mecca.

Notable Minerals

Mesolite (silky white needle bundles), scolecite (clear prismatic radiating sprays), chabazite (rhombohedral pseudocubic crystals), stilbite (sheaf-like aggregates, peach color), heulandite (coffin-shaped tabular crystals), apophyllite (cubic green and clear crystals — gem grade), prehnite (botryoidal apple-green), natrolite, calcite, quartz, agate.

Collector Notes

Indian zeolite specimens from Maharashtra are the global zeolite-collecting standard, supplying the bulk of museum and gem-trade material. Active quarrying continues to surface new gem pockets.