In Balck soils, Chernozem & Grummosols which type of clay are mainly found

Black soil is an expansive type of soil, mainly consisting of montmorillonite type clay minerals.
Black soils are mineral soils that have a black surface horizon, enriched with organic carbon that is at least 25 cm deep.
It is fine textured and clayey which makes it highly retentive of water. It has high amounts of lime, iron, magnesium and generally low quantities of phosphorus, nitrogen and organic matter.