Beveled Glass
Beveled Glass is common, but special in antique mirrors, and window glass. By grinding a bevel all around the glass it cchanges the way the glass reflets and refracts light. It also weakens the edges, so a lot of antique beveled glass has been damaged.
Beveling is also used on modern glass to achieve artistic effects. Below are shown some current Ebay beveled glass auctions that illustrate the variety of glass products for sale which make use of beveling for part of their appeal. If you click on one of those links you will go directly to that auction on Ebay.