"Skates & Rays are a bottom dwelling fish related to the shark family and as such have cartilage instead of bones. They are shaped like a kite and although colors vary, most Skate are a brownish gray color. Skates are larger than Rays and have longer, more pointed snouts. Their “wings” are composed of multiple strips of flesh separated by strips of cartilage. Size varies greatly by species with the largest Skate reaching weights up to 200 pounds, but average commercial size is about 8-10 pounds whole fish."
Source: Chef’s Resource