Marquise Amethyst Bypass Ring with .50cttw Channel-Set Diamonds in 10k Yellow Gold

A marquise amethyst, a medium purple, held on the diagonal in a raised white-metal V-prong head at the centre of this ring. Two tapering arms sweep past it in a bypass — one above, one below — each channel set with round diamonds, four on one side and five on the other, nine stones totalling .50 carat. The arms narrow into a plain polished shank. 4.00 grams of 10k yellow gold.

A bypass ring is the one design that looks like it is moving on a still hand: the two arms never meet, so the eye follows one up and the other down and lands on the stone leaning between them. Setting the marquise on the diagonal is what makes that work — its points carry the line of each arm through the middle instead of stopping it. Half a carat of channel-set diamonds is a good deal more than an amethyst ring usually gets, and it is why this one reads as jewelry rather than a birthstone token. February’s stone, on a ring that does not sit still — whose birthday is it, anyway?