Mudcat Café message #2786639 The Mudcat Café TM
Thread #112030   Message #2786639
Posted By: Rowan
11-Dec-09 - 11:36 PM
Thread Name: Folklore: Pewter Tankards
Subject: RE: Folklore: Pewter Tankards
From various sources.

While the term pewter covers a range of tin-based alloys, the term English pewter has come to represent a strictly-controlled alloy, specified by BSEN611-1 and British Standard 5140, consisting mainly of tin (ideally 92%), with the balance made up of antimony and copper. Significantly, it is free of lead and nickel. Although the exact percentages vary between manufacturers, a typical standard for present-day pewter is approximately 91% tin, 7.5% antimony and 1.5% copper.

From the 15th century onwards, the composition of English pewter was carefully protected by the Worshipful Company of Pewterers in London. The Company required that the finest quality English pewter contain at least 94% tin, with the balance made of other metals including lead. Lead was removed from the composition in 1974, by BS5140, reinforced by the European directive BSEN611 in 1994.

Until the end of the 18th century, the only method of manufacture was by casting and the soldering of components [almost all solder at the time would have had a considerable lead content]. From the last quarter of the 18th century, improvement in alloys and techniques allowed objects to be made from pewter by stamping and spinning

It was known as " fyne peauter " and used for dishes, saucers, platters, chargers, and for all " things that they make square," such as cruets, chrismatories, &c., which owing either to the rough usage they would be submitted to, or to the sharpness of their angles, called for greater toughness in the material . The recipe for this alloy as originally propounded was as much brass to the tin " as it wol receiuve of his nature," but the lack of precision in this perhaps rendered it difficult to distinguish accidental variations from deliberate adulteration, and in 1474–1475 it was resolved that 26 lb of brass must be mixed with every hundredweight of tin. The penalties for infringement of the rules were severe and frequently enforced, but in spite of them alterations and improvements crept in. The chief and perhaps the earliest of these was the addition of a certain proportion of bismuth, or as it was then called " tin glass." When this was first used is not recorded, but by 1561 it was accepted as a matter of course; in 1630 a maker " was found in fault for not sufficiently tempering his metal with tin glass "; and in 1653 it was ordered that 3 lb weight of tin glass at least must be mixed with every 100 lb of tin.

Antimony was subsequently introduced—though there is no mention of it in the records of the Pewterers' Company—sometimes alone as in tin and temper (r.6 to 150 parts) and trifle (17 parts to 83 of tin)—sometimes with other metals as in hard metal (96 parts of tin, 8 of antimony and 2 of copper), a mixture very closely resembling that still used under the name of " Britannia metal," an alloy composed approximately of 93 percent tin, 5 percent antimony, and 2 percent copper, used for making various utensils, including teapots, jugs, drinking vessels, candlesticks, and urns, and for official maces. Similar in colour to pewter, britannia metal is harder, stronger, and easier to work than other tin alloys; it can be worked from sheets, like silver, or spun on a lathe. The alloy is first mentioned in 1769, as "Vickers White Metal," but it was during the 19th century that the advantages of britannia metal were appreciated.

Lots of lead, therefore in antique pewter but none in modern pewter and no mention of cadmium anywhere. Acids in liquids would certainly leach copper out of modern pewter. Stainless steel (90Fe, 10Cr, < 0.5Mn + 0.25C or 90-2Fe, 8Cr, 0.4Mn, < 0.12C or 86.7Fe, 12.5Cr, 0.35Mn, 0.35Ni, 0.12C) may have nickel, to which some become allergic.

More on alloys.

Cheers, Rowan