Clintonite is a phyllosilicate - Monoclinic - Mica group member. It is a brittle Mica - Trioctahedral. Ca, Na, K occupies the Interlayer (I) positions while Mg, Fe2+, Al, Fe3+, Mn in the octahedral positions.
It occurs as tabular, pseudohexagonal, foliated crystals in association with calcite, idocrase, grossular, spinel, phlogopite in crystalline limestones i.e. Crestmore (Encycl. of Min.).
