Template:POTD/2023-09-09
Blairmorite is a very rare porphyritic volcanic rock named after the community of Blairmore in southwestern Alberta, Canada. It is characterized by dominant phenocrysts of analcime in a matrix of analcime, sanidine and alkalic pyroxene, with accessory titanite, melanite and nepheline. It is a leucocratic variety of analcimite. Blairmorite is known from only two geological formations worldwide: the Crowsnest Formation in Alberta, where it is associated with agglomerates and tuffs from explosive eruptions, and the Lupata Gorge in Mozambique. This specimen of blairmorite, found in the Crowsnest Formation, is about 17 centimetres (6.7 in) in length.Photograph credit: Paul Glombick; edited by Bammesk