Muscovite mainly stable as maximum upto the the upper zone of the AMPHIBOLITE FACIES nearly about 600°C temperature and further increase of temperature cause a MUSCOVITE BREAKDOWN ...
This pelitic assemblage is characteristic of Amphibolite facies mainly. It cannot be granulite , as you might be knowing already that in granulite facies dehydrated mineral assemb...
IT'S NOT GRANULITE AS GRANULITE DOESN'T CONTAIN HYDROUS MINERAL LIKE MUSCOVITE.
NOT HORNFELS OF PYROXENE AS PYROXENE NOT PRESENT.
NOT EVEN GREENSCHIST AS NO CHROLITE ,EPIDOTE LIK...