Pewter objects

Pewter. Modem pewter may have a composition of 90—95 wt % tin, 1—8 wt % antimony, and 0.5—3 wt % copper. Lead should be avoided by contemporary craftsman because it causes the metal surface to blacken with age. Pewter metal can be compressed, bent, spun, and formed into any shape, as weh as being easily cast. A wide variety of consumer articles ate available from domestic and foreign manufacturers. Reproductions of pewter objects from colonial times, some cast from the original molds, ate popular. The annual U.S. production of pewter exceeds 1100 t. 

As mentioned above for pewter objects, the corrosion products may maintain the shape of the object even though no metal is left. One of the best examples of this is observed in cast irons. The iron phase (ferrite) corrodes to form the same corrosion products as already stated above. The graphite flakes in the cast iron are inert and trap the corrosion products and the shape is maintained. This is called graphitisation of cast iron and almost all cast iron artefacts recovered from archaeological sites have graphitised layers on their surface. 

Many of uses of tin are also those of lead, because the metals form useful alloys. When lead is alloyed with a few percent of tin, it becomes harder and more durable. Although other compositions are produced, common solder consists of about an equal mixture of tin and lead. An alloy known as type metal contains about 82% Pb, 15% Sb, and 3% Sn, and pewter contains approximately 90% tin that is alloyed with copper and antimony. Babbitt, an alloy used in making bearings, contains 90% Sn, 7% Sb, and 3% Cu. Tin is also used to coat other metal objects to retard corrosion, and a tin-niobium alloy is used in superconducting magnets. 

Tin and lead are often used together in a variety of useful alloys, partly because the presence of a few percent of tin mixed with lead causes the alloy to be considerably harder than lead is alone. For example, common solder consists of about 50% Sn and 50% Pb. Type metal consists of about 82% Pb, 15% Sb, and 3% Sn. Pewter, an alloy used to make ornamental objects and vessels for food and beverages, consists of about 90% Sn with the remainder consisting of copper and antimony. Large quantities of tin are used as a coating for other metals, particularly steel, to retard corrosion. Alloys used as bearings often contain tin, antimony, and copper or aluminum. One such alloy is babbit, which consists of 90% Sn, 7% Sb, and 3% Cu. Several other commonly encountered alloys have various specialty uses. 

Tin has a long, colorful history. This metal was discovered first in Thailand over 2000 years ago. Early craftsmen discovered that bronze - a noncorrosive metal that is extremely hard and strong enough to be used for spears, swords, arrows, and other especially important objects at that time - could be produced by smelting tin with copper. Tin is also the primary constituent of pewter. Long ago, people developed the belief that trace amounts of tin seemed to help prevent fatigue and depression, and that drinking out of tin cups could help combat these ailments. Tin... 

Art, for the most part, makes hermaphroditical, that is, mixt figures, as partly Artificial, and partly Natural for Art may make some metal, as Pewter, which is between Tin and Lead, as also Brass, and numerous other things of mixed natures in the like manner may Artificial Glasses present objects, partly Natural, and partly Artificial.112... 

The first metal spinning in this country was done by silversmiths, like Paul Revere, who used the process to spin bowls, goblets, pans, and other objects necessary for daily life in that era. Parts were made from metals like pewter, copper, brass, silver, and gold. 

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