Orange brown crystals of the rare REE mineral karnarsurtite-(Ce) from the TL in Karnasurt, Russia (Karnasurt Mountain, Lovozero Massif, Murmansk Oblast, Russian Federation). Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY-SA 4.0
Karnasurtite-(Ce)
Karnasurtite-(Ce) is an IMA-recognized mineral species in the silicate class, with the chemical formula CeTiAlSi₂O₇(OH)₄·3H₂O.
Key properties: Mohs hardness 2; specific gravity 2.89–2.95; Yellow streak; Greasy luster; optically uniaxial.
IMA symbol Ksu-Ce, IMA status: questionable, named in 1959.
Found in the intermediate replacement zone, composed largely of microcline, of a zoned pegmatite stock in a differentiated alkalic massif (Mt. Karnasurt, Russia).
It is found associated with Manganoan pectolite, natrolite, epididymite, polylithionite, ussingite.
The name is derived from the locality, Mt. Karnasurt, Kola Peninsula, Russia, and its high cerium content.