2013

Mineralogy of carbonate-zeolite veins associated with Khibina carbonatite, Kola peninsula

Akimova E.J., Zaitsev A.N.

 St. Petersburg State University, St. Petersburg, Russia

Carbonate-zeolite veins, studied in the present work, occur in the eastern part of the Khibina complex and are associated with apatite-aegerine-biotite phoscorites and diverse carbonatites., Their mineralogical composition is however of special scientific interest and mineralogy of the zeolite-carbonate veins was studied in detail. Presented are the results from an  X-ray diffraction investigation of single mineral grains and bulk samples.

This veins have a width of 0.1 to 3 cm. They are fine- to coarse-grained rocks and composed mostly of silicate and carbonate minerals, with subordinate sulphides. The rock textures are banded and spotted. The contacts of veins with rock vary, often abruptly. Grain size is variable, with some minerals forming microcrystalline aggregates, powdery masses, and large elongated or isometric crystals.

23 minerals were found in the studied samples, including: natrolite, ankerite, calcite, rhodochrosite, microcline, nordstrandite, davsonite, fluorite, pyrite, galenite, sphalerite, kutnohorite, burbankite, edingtonite, thomsonite, harmotome, carbocernaite, strontianite, ancylite, norsetite, huntite and shortite.

The crystallization of minerals begin with natrolite, with the subsequent formation of carbonates ending with a variety of rare zeolites such as edingtonite, harmotome and thomsonite.

This work is supported by St Petersburg State University.