Real silverplate, also known as Sheffield plate, is a process that fuses a bar of silver to a bar of copper. The fused bars are then rolled to produce a sheet that has one side of pure silver. This sheet is used to make various items with the silver on the outside to give the appearance of pure silver. Electroplating is a process used to deposit a layer of silver on a cheaper metal, also to give the appearance of pure silver.
In a desire to produce items that had the appearance of pure silver but at a reduced cost, Thomas Boulsover produced the first "silverplate" in 1743. He fused a bar of silver to a bar of copper in a furnace, then rolled the bar through a calendar press or hammered it to produce a sheet. The resulting sheet had one side of pure silver. Alternatively, the silverplate could be made with an ingot of silver on both sides of the copper ingot. Pieces made in either fashion are known as "Sheffield plate" for the region where this technique arose. The name "silverplate" was also used to describe Sheffield plate.
Electroplating is a chemical process that allows a coat of silver to be deposited on a cheaper metal item. In this method, the metal item is placed in a bath containing dissolved salt of silver such as silver nitrate. The metal item is connected to a negative electrode, and positively charged silver ions are attracted to the metal ion when an electric current is induced. The silver ions coat the metal ion and are reduced to metallic silver. Electroplating replaced Sheffield Plate in the 1840s as a cheaper alternative. Electroplating with silver is now known as silverplating, leading to some confusion with the completely different process used to produce Sheffield plate.
Characteristics of Real Silverplate
Sheffield plate often has seams that show where the copper and silver have been fused. Sometimes a coating of silver solder was used to hide this seam, or a flattened silver wire was applied to hide the seam. Sheffield plate that has been engraved will often show the inner layer of copper through the engraving. Sometimes a pure silver oblong was inserted into the sheet so the engraving would not show the copper. More often, Sheffield plate was not engraved.
Charactericstics of Electroplate
Electroplate can give a more uniform silver finish than silverplate. There are usually no seams with the underlying metal visible. The base metal is usually either copper or nickel. Thin electroplating can be worn off, showing the base metal below. Items can also be re-electroplated. Electroplated items are much cheaper to produce than Sheffield plate, and are usually less desirable as collectibles. When Sheffield plate ceased most production after 1851, electroplating began to be called silverplating.
British silver is hallmarked to show the purity of the silver, where the piece was made and the maker of the piece. However, Sheffield plate often is unmarked. It is more definitive to examine the style and quality of the piece to determine when, where and by whom the piece was made. Sheffield plate process was rarely used after the year 1851. Decorative styles used for Sheffield plate include rococo, neoclassical, regency, gothic, Victorian and naturalistic.