Object Type
This is a demonstration sample of a Sheffield plate ingot at the stage just prior to being heated and fed through a graduated set of rollers to produce a flat, laminated sheet.

Materials & Making
The process developed by Joseph Hancock (1711-1790) for large-scale production of fused (Sheffield) plate has differed little throughout the course of the industry. An ingot of copper, alloyed with a small percentage of lead and zinc, was covered with a thin sheet of sterling silver. These ingots were approximately 1« to 1_ inches thick and 2« inches wide by 8 inches long (4 x 6 x 20 cm). This could vary according to the weight and size of the plated sheet that was required to be made. Generally speaking, however, the thickness of the silver sheet was 1/40 that of the copper block, which meant that 10 to 12 ounces of silver were used for every 8 lbs of copper.

People
After about 1760, it became the practice to plate two sides of the copper ingot so that the resulting sheet was plated with silver on both sides. In 1830 Samuel Roberts (1763-1849) patented a variation (no. 5963), whereby a sheet of German silver (an alloy of copper, zinc and nickel) was inserted between the silver and the copper block. This produced a laminate of far greater durability. An improved version of Roberts's development was patented (no. 7018) by Anthony Merry, a Birmingham metal dealer, in March 1836. This dispensed with the copper and brass substrates altogether, the silver being plated onto an improved quality German silver where the base metal alloy was whiter than formerly and less likely to split under pressure.