Nepheline tutorial Optical mineralogy
Channel: Matt Kohn
Date: 05/05/2021

Three videos of nepheline in thin section, showing typical textures and optical characteristics. Supported by Boise State University and the US National Science Foundation.
Key characteristics: low relief, very low interference colors, occurs in SiO2-poor (highly alkaline) igneous rocks.
00:00 In rock with sodalite and K-feldspar, has apatite inclusions
00:31 Closeup of region with apatite inclusions
01:02 Large crystal