Amorphous aluminosilicate minerals like allophane have . . . . . . . . negative charge, which is partly or entirely balanced by complex aluminium cation

Solution (By Examveda Team)

Allophane is amorphous to poorly crystalline hydrous aluminum silicate mineraloids. Its chemical formula is Al₂O₃·(SiO₂)_1.3-2·(H₂O)_2.5-3 . It is produced by weathering or hydrothermal alteration of volcanic glass or feldspars. It has a large negative charge, which is balanced by aluminium cation.