With his closet full of blazers and professional demeanor, jewelry designer Niveet Nagpal might be taken for a real estate executive or finance guy—were it not for a rather conspicuous brooch in the shape of a gecko that habitually clings to his lapel. “This is Alexis. She’s my signature piece,” he explains of the 18k white gold lizard, whose slender back is encrusted with alexandrite (her namesake) and who stares unblinking at him with tsavorite eyes and a flick of a ruby tongue, her legs wiggling slightly when he walks. Ring with 10.23 ct. oval cup