Bird's eye extinction
Bird's eye extinction, or bird's eye maple, is a specific type of
crystal lattice
, leading to this type of extinction. Since it is not a natural feature of the mineral, bird's eye extinction is not observed in all mica crystals, nor from all angles, but it is quite common, and is used as a diagnostic feature for micas.
Common
.References
- ^ Smith College - Geology 222b - Petrology - Petrographic Data File - Biotite Archived 2013-05-10 at the Wayback Machine Retrieved 2015-07-02