Mineralogy of sand, silt and clay fraction in the selected horizons of rice growing and adjacent virgin soil profiles from north-west Himalayan region (Kangra district, HP) does not show much difference. The light sand fraction is predominated by quartz, feldspars and muscovite mica and that of heavy sand by opaque minerals, zircon and tourmaline (⩾ 60%). Orthoclase, plagioclase, augite and hornblende are of weathered nature. Silt fraction contains mica, feldspars, quartz and chlorite. In the clay fractions, mica or illite are the dominant clay minerals followed by chlorite, kaolinite and mixed layers, as well as amorphous SiO2 and Al2O3. Mica is di-and trioctahedral in nature and chlorite is trioctahedral.
Minerals in sand, silt and clay fractions, north-west Himalayan soils
