At an exhibition on Island Peoples at the Fizwilliam Museum today, there were two samples of Covellite, also known as covelline. It is a rare copper sulfide mineral with the formula CuS. Also, two ‘ox hides’ I think they were called. They were not the hide of any animal but rather the shape is reminiscent of the hide of an animal. In fact there are ingots of bronze or copper wide enough for a man to carry on his back, holding on to them by the spurs at the ends of the block. They were made to a certain standard size so they could be used as trade goods with a specific value owing to their known size.