For Higashi Jewelry & Eyewear owner Susan Fotos, sapphires and spectacles make ­fantastic bedfellows. Her 1,500-square-foot store in Lemoyne, Pa., not only sells fine jewelry but also includes a full optical shop—complete with on-site ­ophthalmologist—offering frames from swank eyewear makers including Tom Ford, Oliver Peoples, Persol, Prada, and Tiffany. A lifelong fan of cool specs, Fotos started stocking readers, then sunglasses, about five years ago. The side business, which she calls “crazy fun,” took off quickly. “Glasses can change your look faster than any piece of jewelry,” Fotos adds. “They really communicate who you are.” And the nontraditional product pairing distinguishes Higashi from other jewelry outposts. “I’m competing with a local store that has Rolex and John Hardy,” says the retailer, “so I’ve really concentrated on carrying things that