Pelite
“Metamorphosed mud with a mineral story to tell”
Pelite is a general term for fine-grained metamorphic rocks derived from clay-rich sediments like mudstone and shale. As temperature and pressure increase, pelites develop a progressive sequence of index minerals — chlorite, biotite, garnet, staurolite, kyanite, sillimanite — making them invaluable for mapping metamorphic intensity.
quartz, muscovite, biotite, garnet, staurolite, kyanite, sillimanite (varies with grade)
Scottish Highlands (Barrovian type locality), Appalachian Mountains, Alps, Himalayas, Otago (New Zealand)
3-7 (varies with grade)
George Barrow's pioneering 1893 study of pelites in the Scottish Highlands established the concept of metamorphic zones — a framework geologists still use worldwide today.
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