An extended metal oxide possessing a cationic charge on the host has been synthesized by hydrothermal methods. The structure consists of 1D antimony oxide [Sb6O2](4+) chains with a new structural motif of four Sb atoms wide and unprotonated sulfate anions between the chains. The material was characterized by powder and single-crystal X-ray diffraction. Thermal behavior and chemical resistance in aqueous acidic conditions (pH similar to 2) indicate a highly stable cationic material. The stability is attributed to the entirely inorganic composition of the structure, where 1D covalently extended chains are electrostatically bound to divalent anions.