Mineralpedia Details for Kaersutite
The type locality at Qaersut, which was formerly called Kaersut, in Greenland, is the namesake for this mineral. It occurs “as phenocrysts in alkalic volcanic rocks, in gabbroic and peridotitic nodules in alkalic basalts, in syenites, monzonites, carbonatite tuffs, and alkalic gabbros.” Localites include in Greenland, Italy, the Czech Republic, the United States, Canada, Japan, and New Zealand among other localities.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/kaersutite.pdf
Kaersutite from Nickenicher Sattel, Eifel Mountains, Germany
Orange long thin prismatic Kaersutite crystals to 3mm long covering volcanic matrix.