Black glass plare/saucer 6 1/2" dia. made by the West Side Glass Co in Bridgeton NJ. Ferroline Opaque black glass was patented by Enrico Rosenzi and Benjamin Lupton in 1881. Ferroline is a combination of the Latin word ferrum (iron) and 'opaline. Thier glass was advertised as indestructible and was used for tiles and table tops,lamp feet,vases and plates. The factory burnrd down in 1885. This perticular plate has a 3D rose in the center. Bridgeton became famous for the "Bridgeton Rose" paperweight made by Ralph Barber a gagger that was imployed at the Whital Tatum Glass factory in Millville NJ. Ferroline glass is not common. Typical roughness at edges from early glass pressing methods.