CPOD from 2020/03/25
Scanned image of thin section from Siilinjärvi apatite ore in cross polarised transmitted light. Actual sector size about 37 × 20 mm.
Artist: kallerna; License: CC BY-SA 4.0; Credit Own work
See explanation at https://commons.wikimedia.org/wiki/File:Thin_section_scan_crossed_polarizers_Siilinj%C3%A4rvi_R636-105.90_edit.jpg









