1881 turquoise and diamond three stone ribbed ring

1881 turquoise and diamond three stone ribbed ring in 18kt yellow gold. Set across the finger with three round cabochon cut turquoise in four claw collet settings, alternating with four vertically set cushion shape Old Mine cut diamonds in collet settings, to a tapering band design with square inset collets, flanked to either side with integrated deeply incised shoulders, met to top and bottom with polished recessed borders and tapering to a polished solid shank. Hallmarked 18kt gold, London, 1881. Engraved to the inner 'A.L & J.B 1895'.