Shark skin, used to be used for sand paper, before sand paper came along. If you are going to use them for a grip, I would recommend you sand down the dentiles, or little teeth on the skin like they do with ray skin. Other wise, you will be getting big callouses and scratches. As for the meat, it is high in uric acid. You can soak it in a solution of water, & salt, in the refrigerator, over night. Some people soak the meat in milk. Anyway, the fish n chips in England, I have read is actually shark. As for sand paper, in the Virgin Islands, there is a museum on St. Croix, in the U.S. Virgin islands,called the Whim House. It had the only still functioning wind mill. Really neat place. They still had the original out buildings, work shop, and an "Apothecary" shop, with original medical books, and original microscope, and bottles, still filled with medicine, and a huge bowl carved out of lime stone, with a clay bowl under neath that. They would poor water in the limestone bowl, and the water would leach through it, and drip into the clay bowl, and you had pure water. Also they wanted you to sit in the chairs, lie down on the beds, etc., to see what if was like back then. These were late 1600-late 1700's period furniture! Absolutely beautiful, and amazing craftsmanship! Anyway,like I said, they have all the original out buildings, as well, and still stocked with the original tools, and even have an original letter from Alexander Hamilton's order for products there, mainly sugar, and molasses. And they had some trigger fish skins hanging up, and a description explaining these were used as sand paper. I don't know if it is still standing, or not I can't remember which hurricane, Hugo? That went through there and did a lot of damage, so I don't know if the place is still standing or not.
Wayne