I've been looking for a smaller asscher-cut or square-cut emerald diamond, approximately 5 x 5 millimeters for a project. I saw a .90 carat stone today in a local store that came out of a broken 1920s deco setting. I looked at the diamond under the store's microscope and I saw what appeared to be a culet in the center of the stone. There was a small square in the middle of the stone. Is it possible for an emerald or asscher cut stone to have a culet? Or was I seeing something else?