Isomorphism of basic copper chromate, CuCrO₄2CuO.2H₂O, and antlerite, Cu₃(SO₄)(OH)₄

The similarities of the observed and calculated powder X-ray diffraction patterns show that CuCrO₄.2CuO.2H₂O is isomorphous with Cu₃(SO₄)(OH)₄. In an unusual replacement chromium substitutes for sulfur.