Mt. Pyalkimpor, Lovozero Massif, Kola Peninsula, Russia
Calciomurmanite is Na-Ca ordered analogue of murmanite. Murmanite does not contain calcium, only Na, by strict definition. Otherwise, you cannot tell these two minerals apart visually. Calciomurmanite crystals occur as thin plates and somewhat micaceous. The cleavage surfaces have a mother of pearl luster. This specimen was verified by Dr. Igor Pekov and was part of his study to define the mineral for publication. It is an approved IMA mineral, although not yet published.