This is a souvenir ashtray. The base is made of an acrylic / lucite material and has what looks like shell pieces inside. It is marked: Yellowstone Nat'l Park. The ashtray is a blue glass. The base is about 6 3/4" x about 5 1/8" measuring across the bottom. The ashtray does have a crack in it, conditon; good pre-owned. ashtray has a crack, and base has several chips. #yellowstone park #souvenir #ashtray