Chloritoid tutorial Optical mineralogy
Channel: Matt Kohn
Date: 03/05/2021

Several videos of chloritoid in thin section, showing typical textures and optical characteristics. Supported by Boise State University and the US National Science Foundation.
Key characteristics: Very high relief, blue pleochroic, twins, very low interference colors.
00:00​ Typical porphyroblast
00:30​ Good pleochroism, high relief
01:01 Spray/cluster of crystals
01:31​ Comparison to staurolite
02:02​ Deformed grain