Cowlesite crystals from Antrim Co., Northern Ireland, UK – micromount as unique piece
This micromount specimen features Cowlesite crystals from Antrim County, Northern Ireland, UK. The specimen consists of a dark basaltic matrix containing numerous cavities in which light colored to white Cowlesite crystals have formed. Particularly striking are the fine spherical to crust like crystal aggregates within the vesicles of the volcanic rock. The delicate crystal formations create an attractive contrast with the dark matrix and appear especially detailed under magnification. For zeolite collectors, Cowlesite is an interesting collector mineral because of its rarity and delicate crystal habit.
Geology & origin
Antrim County in Northern Ireland is world famous for its extensive volcanic basalt formations. Numerous zeolite minerals formed within gas cavities of these basalts through hydrothermal processes. Cowlesite belongs to the rare zeolites and usually forms fine white crusts or spherical aggregates in cavities of the host rock. Specimens from the classic basalt localities of Northern Ireland are especially appreciated among collectors of British zeolite minerals.