Kakortokite: Gemstone Information
Kakortokite is the name given to an ornamental rock found in the Julianehaab area of southern Greenland. The varied colours arise from the different minerals in its composition: white nepheline, black arfvedsonite and red from crystals of eudialyte (q.v.) which occurs in the nepheline. The SG of the rock is 2.7–2.8.