Here, 30 stunning opal engagement rings for the unconventional ... One of a kind diamond tennis opal ring in 18K gold, $5,790, ireneneuwirth.com. Micro pave diamonds surrounding this pear-shaped ...

1.25 Carat Round Cut Color Moissanite 14k Rose Gold Diamond Engagement Ring There's no doubt they'll feel like royalty with the round opal and marquise stones on the Skylar Ring With Opal ($380).