Robert Marc is a very high-end line of eyewear. I believe he started as an optician and then developed his line of frames for regular and sunglasses. All of his frames feature a sterling silver hinge on the temple.
I just bought a new pair of prescription sunglasses at a very hip eyeglass place in Western NY. I was deciding between a pair of Robert Marcs and a pair from another designer. (Shoot... can't think of the name...) Anyway, the assistant told me that RM is "very New York" while the other one (which was more golden-tone) was "more LA." I went with the Robert Marc. They're BIG, with dark tortoise on the exterior of the frame and they're lined on the inside in pale pink. So pretty!