THE NEW AMPHIBOLE POTASSIC CHLOROPARGASITE (K, Na)Ca_2(Mg,Fe~(2+))_4Al(Si_6Al_2O_(22))(Cl,OH)_2 AND CONDITIONS OF ITS FORMATION IN THE GRANULITE COMPLEX OF SAL'NYE TUNDRY MASSIF (KOLA PENINSULA)

摘要

Potassic-chloropargasite, a new mineral of the amphibole group, has been found at Elgoras Mt. In the granulite complex of the massif Salnye Tundry, Kola Peninsula, Russia. The mineral occurs as black grains up to 0.5mm and is associated with chlorapatite, almandine, diopside, enstatite, Cl-rich biotite, potassic pargasite, marialite, plagioclase. Mohs' hardness is 5.5. Biaxial, negative, alpha=1.675(1), beta=1.687(1), gamma=1.690(3), 2V_(calc)=53 deg, 2V_(meas)=65(15) deg. Pleochroism: alpha(light-grey)