Vintage Mens Oval Black Onyx Signet Ring. The item "Hallmarked 9ct Gold Vintage Mens Oval Black Onyx Signet Ring 3.9g Size U1/2" is in sale since Saturday, February 13, 2021. This item is in the category "Jewellery & Watches\Men's Jewellery\Rings". The seller is "jbclearances2012" and is located in sheffield, South Yorkshire. This item can be shipped worldwide.