Tin device
When pewter is referred to the budget - and everyday objects such as tableware (plates) and cutlery , vases and ornaments , from tin alloy ( pewter or Britannia metal ) were prepared. In South German, the term pewter dishes is generally used for all pewter utensils.
history
Tin utensils have a long tradition and have been documented for around 2000 years, even if a few very old pieces (e.g. as grave goods ) have been preserved, as the material was melted down again and again when the device was no longer usable. Church tin utensils, which less well-off parishes used, have been preserved in particular.
Because of its resistance to corrosion, tin was used whenever silver was too valuable. Pure tin has a silver sheen and similar positive properties when it comes to food resistance. Original pewter utensils have little in common with the mostly artificially aged historicizing decorative objects of our day. Pewter utensils were often utensils on which overloaded ornaments would have been a nuisance. But it did show the prosperity of the bourgeoisie and rich peasants; it was the little man's silver, so to speak. In addition, damaged tin utensils (unlike broken ceramics) could be repaired. Even if repairs were no longer possible, a tin object that had become unusable still had a material value, it could be melted down and re-cast.
Manufacturing
Most tin equipment is poured. Tin can be processed in all common casting processes (e.g. sand, permanent mold, centrifugal, die casting ). But pressing , especially extrusion for cups and the like is also common. a. rotationally symmetrical parts. Hammering and driving is less common. Individual parts are often joined together by soldering . Burrs or unclean surfaces are reworked using machining processes such as turning or grinding.
It was already common in earlier times for pewter foundries to stamp their products with a stamp that guaranteed the quality of the material and named the producer.
Care of the tin device
Lead-free tin is tarnish-resistant to a high degree, patinated (aged) tin utensils only change very slowly. Tin equipment that is not in constant use should be dusted regularly, as moisture in the dust can cause corrosion. Commercially available detergents without bleaching additives are suitable for washing. When cleaning in the dishwasher, the color may change. Since tin is a soft metal, only use soft cloths.
Tin alloy and lead content
Pure tin is absolutely safe for food. However, tin is almost always processed as an alloy because it is easier to process, has higher strength and to avoid tin plague . Common alloys are alloys with antimony and lead (especially for solders). The toxicity of lead compounds has been known since the Middle Ages at the latest. Lead salts are particularly poisonous, as they can come into contact with food (fruit juices, wine, vinegar ...). The alloy therefore usually had a lead content of no more than 10% (e.g. the English Pewter ), which was monitored by the guilds. Pewter dishes with this relatively high lead content are rarely found, as it was customary to melt down old, discarded pewter equipment for new ones. The largely lead-free Britannia metal appeared in England in the 18th century .
Since the zinc-lead law of 1887 , tin utensils that are used for food may only contain small amounts of lead in Germany. The limit was later set at a maximum of 0.5% lead (max. 2% copper, max. 7% antimony). In simulations with citric acid, beer and cola, 0.3–0.9 ppm lead was detected in the solution after 24 hours of contact at 20 ° C. However, since traces of lead accumulate in the body, this harness (according to DIN 17810) should no longer be used. Even the angel with scales (old RAL seal of approval ) is not a seal of approval for harmlessness today. New pewter dishes for use with food must not contain or give off lead.
Recycling
Interest in pewter tableware is currently low, while it was a popular collecting area back in the 1980s. With household resolutions, smaller and larger collections are freed up again and again. Experience has shown that even beautiful pieces from the period after 1950 can usually only be sold for their material value, only older objects are traded as antiques . However, caution is advised, since at times of great demand imitations were also produced, which are sometimes difficult to recognize as such.
Tin is now one of the most expensive non-ferrous metals in households and is therefore bought by specialized companies.
literature
- Aichele, Frieder: Zinn , Battenberg antiques catalogs, Battenberg Verlag, Munich 1977, ISBN 3- 87045-131-9.
- Müller, Berthold F. (ed.): Zinn-Taschenbuch . Metall-Verlag, Berlin 1975, p. 163ff.
