Mineral: Fluorapatite
Locality: Huron River, Ohio, USA
Dimensions: 1 mm crystal
Description: Unusual sector zonation revealed by crossed polarizers and a gypsum plate. Different colors represent different optical orientations within the crystal, aligned with different growth sectors. (This is not supposed to happen!) One half of a platy hexagonal crystal is shown.
All pictures, text, design © Forum FMF 2006-2024