Description :
Photomicrograph of corona textures around garnet in Sil-Grt-Bt-Crd paragneiss from the Grand Forks Complex, B.C. Cordierite forms an innermost reaction zone, with quartz forming an outer rim. Corona texture a function of rapid, near-isothermal decompression in the complex. Sillimanite, cordierite, and ilmenite are found in altered mesosome at the bottom of the photo.