Heavy minerals from the Siwalik formations of the northwestern Himalayas

The heavy-mineral assemblage of the Siwalik sequence consists of zircon, tourmaline, rutile, garnet, chlorite/chloritoid, staurolite, epidote, biotite, kyanite and sillimanite. The opaque fraction constitutes a sizable proportion of the heavies and includes magnetite, hematite, limonite, ilmenite, rarely pyrite and sporadic chromite. Staurolite is the marker for the Lower Siwaliks, the appearance of kyanite marks the base of the Middle Siwaliks while the Upper Siwaliks are characterized by the presence of sillimanite in addition to the heavy-mineral assemblage encountered in the Lower and Middle Siwaliks.