The stunning sapphire is set in the center of a halo of high-quality diamonds

The double face really displays the banding in the onyx

such as this one

polished ring would look equally well on a man or a woman

Art Deco "H" Black Onyx Signet Ring inv 3390 The stunning sapphire is setThis vintage black onyx signet ring is absolutely timeless! Crafted in white gold and set with black onyx, the top of this ring is riveted with a letter "H" in Old English. The monogram has the same finely engraved detail as the mounting, giving the piece an ornate look. Metal: 10K White Gold Gem: Black Onyx Gem Measurements: 13. 5 x 11. 5 mm, Cushion Cut Monogram: "H" in Old English Ring Size: 7. 25