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[Roger Warin]

About shocked quartz.
Meteorites do not contain quartz. Whole silicon is inserted in silicates (pyroxenes, olivine and feldspars). So there is no extraterrestrial rock corresponding to the granite.
Shocked quartz is into terrestrial rocks that contain these crystal grains having suffered an impact of an extraterrestrial body. One cannot observe a shocked quartz with the naked eye only under a microscope. These crystals are covered by planar deformation features (PDF's). They are different from planar fractures (PF's), such (00.1) (10.1) and occasionally to (10.3).
The PDF’s are preferentially oriented parallel to numerous crystallographic planes.
Roger.

[Roger Warin]

Hello,
It often appears constraints in the rocks. Here is a crystal that has undergone a planar fracture (PF). This is not uncommon. This fact causes a pseudo cleavage in quartz (which has no cleavage).
Roger.