I love these awesome Space Invader rings designed by Frank Tjepkema, principle of Dutch design studio Tjep. Made from Silver its titled Invader Aiko. I'm not sure on cost, but i believe they are made to order, so not cheap!
I'd totally get this for Justin since emerald is his birth stone. Emerald Green Resin Ring Men Ring Gold Flakes Big Size 10 size 12 Faceted Ring OOAK boho minimalist jewelry deep emerald rusteam by daimblond on Etsy