stripes
Occurrence number:
174-00-010
Country:
United States
Region:
Alaska
Location:
Longitude: -147.1, Latitude: 65.48
Carbonatite:
No
Located 34 km west of Mount Prindle and southeast of the White Mountains is a small badly exposed complex of syenites and nepheline syenites for which few data are available. Drilling indicates gradational contacts between rock types. The syenites vary from K-feldspar-aegirine-augite rocks with a little biotite and locally nepheline and sodic plagioclase, to varieties with quartz, microperthite and riebeckite. Pyroxenites also occur.
Economic:
Highly radioactive zones consist of britholite, allanite, thorianite-uraninite, thorite, monazite and accessories. Analyses of selected material gave up to 25% REE and 15% Th; U seldom exceeded 0. 2%.
References:
ARMBRUSTMACHER, T.J. 1984b. Rare-earth thorium deposits associated with a complex of syenitic rocks near Mt. Prindle, east-central Alaska. Abstracts with Programs, Geological Society of America, 80th Annual Meeting, Anchorage, 266-7
Location: