Plated Ware refers to articles that consist of a base metal or alloy covered by precious metals such as silver, gold or nickel. A wonderful site for reference to all matters relating to silver plate worldwide is www.925-1000.com
Old Sheffield Plate
The original Old Sheffield Plate is a layered combination of silver and copper. The technique was discovered by Thomas Boulsover of Sheffield's Cutlers Company in 1743. While repairing a silver knife with copper, he overheated it melting the silver. He noted that the silver and copper strongly fused together to behave as one metal when he tried to reshape them even though he could clearly see two separate layers. Boulsover set up his own business and used techniques to fuse a thin sheet of silver to a thick layer of copper by heating after which they were hammered or rolled to make a thin layer of silver on the top surface and a thick layer of copper underneath. Almost every article made in sterling silver could then be made as Old Sheffield Plate at far less cost. It was used to make items such as tea and coffee services, serving dishes and trays, soup tureens and candlesticks. Early Old Sheffield Plate was heavy with a fairly plain surface but decoration later became much more extravagant.
The "double sandwich" form of Old Sheffield Plate was developed around 1770 for bowls and mugs that had a visible interior. It consisted of a sheet of silver each side of a piece of copper. Initially, edges were hidden by folding them over, but from about 1790 the borders were covered by pieces of silver wire to conceal the copper which may be felt as a lip on the undersurface, and solid wire was used later which can be hard to detect.
The Old Sheffield Plate process is rarely used today having been replaced by electroplating. This makes these pieces all the more valuable. Silver was cheaper than gold or nickel but the silver layer could be porous or finely cracked causing the silver to flake allowing the underlying copper to be exposed and to corrode. Accordingly, much Old Sheffield Plate seen today has been replated which may be recognised by detecting soldered joints although these were often well hidden by expert repairers. Many Old Sheffield Plate designs have been reproduced as electroplate.
Sheffield Plate
Old Sheffield Plate was gradually replaced by an electroplating process simply termed Sheffield Plate. An electric field drives silver or other metal ions in solution onto a conductive base metal. Electroplating tends to produce a harder more brilliant surface as the outer layer consists of pure rather than sterling silver and is usually deposited more thinly. There are still many firms dealing in electroplate produced in Sheffield.
Electroplated nickel silver techniques became popular to produce more durable goods and these are marked EPNS. This became popular as a base metal for cutlery and other silverware, and is used for making musical instruments. Britannia metal which is a pewter-type alloy composed of approximately 93% tin, 5% antimony and 2% copper was first produced by Sheffield manufacturers in about 1770 under the name of Vickers White Metal and it too could be silver electroplated and is then marked EPBM. A further variation on the technique is Elkington Plate manufactured in Birmingham (see Article)
Plating is also critical for modern technology, for example to decorate objects, inhibit corrosion, improve durability, reduce friction, improve paint adhesion, alter conductivity and shield for radiation. Today, solutions containing gold, silver, stainless steel, palladium, copper or nickel are deposited by dipping an object into the solution and applying a chemical or electrochemical action. This may be for decoration but now more often for automotive parts, machinery, hardware and plumbing or electronic equipment.
Close Plate
Close plate consists of silver foil soldered onto a steel base and was used for items such as candle snuffers or cutlery requiring greater strength than fused plate. Close Plate ware was mostly made in Birmingham in the early 19th century.
Nickel Plate
Nickel was favoured by some German companies such as WMF (see Article) and this gave an even stronger coating. It was best used for goods such as trays or cylindrical items that did not require complex shaping. So called German silver (60% copper, 20% nickel and 20% zinc) was produced from about 1820 and was found to fuse well with sheet silver and provided a suitable base metal for the Sheffield process. German silver showed less wear or "bleeding" when Sheffield-made articles were subject to daily use and polishing. Early in the twentieth century, German silver was used by automobile manufacturers before the advent of steel sheet metal, for example for the Rolls Royce Silver Ghost of 1907.
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