Old Sheffield Plate
The expression 'Sheffield plate' and all variations thereof are generic terms which may apply to any product of silver appearance made in Sheffield, UK.
[2] Boulsover's discovery or invention was to find that sheets of silver and copper under high pressure would fuse together when heated to the melting point of the silver-copper eutectic alloy, then could be rolled out and shaped without the layers separating.
Boulsover set up in business, funded by Strelley Pegge of Beauchief, and carried out further experiments in which he put a thin sheet of silver on a thick ingot of copper and heated the two together to fuse them.
The main centre for the trade was always Sheffield, England, where there was already a substantial manufacturing industry for making small silver items such as buttons, cutlery and snuff boxes etc.
[9] While Boulton's ormolu and solid silver products tend to attract most attention,[10][11] his button and plated wares manufacturing were financially always more important.
Edges of early salvers were hidden by folding them over but from about 1790, borders were applied with U-shaped lengths of silver wire to conceal the copper which can often be felt as a lip on the underside.
Die stamping was used extensively for shaping the basic sheets of OSP and also for forming small parts such as feet and handles.
Electroplating tends to produce a "brilliant" surface with a hard colour – as it consists of pure rather than sterling silver and is usually deposited more thinly.
Sheffield plate continued to be used for up to a further 100 years for silver-plated articles subject to heavy wear, most commonly uniform buttons and tankards.
[citation needed] During the 1840–1850 period, hybrid articles such as sugar bowls were produced, with the body being Old Sheffield Plate and complicated small parts such as the feet and handles made from electroplate.
During the Second World War, a process analogous to Sheffield plating was used to build intercoolers for Rolls-Royce Merlin engines to overcome problems with thermal fracturing.
Collectors should be aware that many designs have been reproduced in electroplate, with those from the early 1900s being the hardest to recognise since, like the original items, they seldom have a maker's mark.
The most important volume to appear in many years, a thoroughly researched work with much detail on the main producers and numerous excellent colour illustrations.
Although published in the early 20th Century, Bradbury is still a valuable source of information, as he was the owner of a plate making company hence directly involved in the trade.
