Gmelinite

A specimen showing light salmon-coloured crystals of gmelinite lining the top of this section of basalt from the quarry at Magheramorne, County Antrim, Northern Ireland. The gmelinite occurs as well-formed crystals and display the soft peach to salmon colouration characteristic of this zeolite species.

Magheramorne Quarry has long been worked for crushed stone and exposes flows of the Antrim Plateau Basalts, a Paleogene volcanic province famous for its zeolite minerals. Gas bubbles trapped in the cooling lava later became cavities that were filled by mineral-rich fluids, forming a variety of zeolite species including gmelinite, chabazite, thomsonite, and others. Specimens from this locality are representative of the diverse mineral assemblages found within the vesicular basalts of northern Ireland.