The Maru schist belt consists predominantly of pelitic to semipelitic metasedimentary with subordinate interlayered
psammites, banded iron formation (BIF) and amphibolites.
At Osprey West, thin quartz +calcite +chalcopyrite veins occur in hole OS13D02 within a succession of metasediments (gneisses,
psammites, psammopelites).
These rocks form the basement on which the Moine Supergroup and Torridonian sediments were deposited The Moine Supergroup consists of a thick and extensive sequence of Neoproterozoic siliciclastic metasedimentary rocks, dominated by
psammites with subordinate pelites (Mendum et al., 2008).
Vicat (1837) presented in the section on Artificial Pouzzolanas: "Under this denomination we shall include the clays, arenes,
psammites, and shists [German term for slate], properly calcined; smithy slag, the refuse of the combustion of turf and coal, and pounded earthenware; and, lastly, tile and pot shards." on p.
The field evidences indicate a sheared contact of Mandi Granite with the Jutogh metamorphic marked by very sharp boundary, where
psammites are intensely sheared.
Reactionary grain boundaries indicate a partial metamorphism to
psammites. Some quartz grains are elongate from stretching during metamorphism.