Probably 1950, about 25mm diameter (U.S. 25 cent coin). Has Ste Croix made very audible tiny cylinder music player built in. Never opened. back screw slots show my attempts. Has genuine snake skin covered side that might be damaged. Maybe someone can suggest how to take down? Works fine. Looks like hi q. Not solid gold. Just 2 crowns serve as feet and manage all functions properly except winding cylinder spring. Expect to see a good grade Bueche Girod 17j lady ww. mvmt.in it with alarm mechanism; alone a rarity.