Antique porcelain Bell telephone sign. Porcelain signs consist of multiple layers of powdered glass which is ground and the fine glass particles are fused color after color. Rolled iron is the base which will be diecut into different shapes. Porcelain signs were made from the 1880's until the 1950's, and telegraphs were used during the 1800's. Our best guess is that this sign is more than 100 years old.