ASTROPHYLLITE SPECIMEN

(K,Na)3(Fe,Mn)7Ti2Si8O24(O,OH)KHIBINA MASSIF, KOLA PENINSULA, RUSSIA

 THIS SPECIMEN WAS MINED IN THE KOLA PENINSULA RUSSIA ASTROPHYLLITE IS A VERY RARE, BROWN TO GOLDEN YELLOW HYDROUS POTASSIUN IRON TITANIUM SILICATE MINERAL. BELONGING TO THE ASTROPHYLLITE GROUP. ITS HIGH, SUBMETALLIC LUSTRE AND DARK COLOR CONTRAST SHARPLY WITH THE LIGHT COLOURED (FELSIC) MATRIX THE MINERAL IS REGULARLY FOUND WITHIN. ASTROPHYLLITE IS USUALLY OPAQUE TO TRANSLUCENT, BUT MAY BE TRANSPARENT IN THIN SPECIMEN. FOUND IN CAVITIES AND FISSURES IN UNUSUAL FELSIC IGNEOUS ROCKS, ASTROPHYLLITE IS ASSOCIATED WITH FELDSPAR, MICA, TITANITE, ZIRCON, NEPHELINE AND AEGIRINE. COMMON IMPURITIES INCLUDE MAGNESIUM, ALUMINIUM, CALCIUM ZIRCOMIUM, NIOBIUM AND TANTALUM. IT WAS FIRST DISCOVERED IN 1854 AT ITS TYPE LOCALITY: LAVEN ISLAND, NORWAY. INTERESTINGLY, KUPLETSKITE WAS NOT KNOWN UNTIL 1956, OVER A HUNDRED YEARS LATER. 

SIZE: 29 X 17 X 10 MM APPROX. 

WEIGHT:25 CTS APPROX.