Novel structure of 2:1 layer formed by dehydroxylation of Fe3+, Mg-rich mica

Abstract

A new modification of the 2:1 phyllosilicate layer has been discovered in annealed celadonite, Fe³⁺, Mg-rich dioctahedral mica.The high-resolution TEM image along the <100> or related directions is similar to that expected from normal micas but the image along the <010> direction is completely different. From these images, it is concluded that the two tetrahedral sheets in a 2:1 layer are facing each other with no lateral a/3 stagger.