Tin and Lead

This is the another in our series of posts on metal-working written by Dr. Kevin Leahy, PAS National Finds Adviser. The articles were first published in The Searcher magazine and are reproduced here with kind permission from Harry Bain, editor for The Searcher.

1: A lead Papal bulla issued by antipope John XXIII (1410-1415). A bulla is a lead seal that was attached to documents issued by the Papal Chancellery. They remained unchanged for centuries, aside from the inscriptions (SUR-91AB24). 2: Lead brooches like this were in use in the late Anglo-Saxon period and are thought to represent copies of silver brooches. Some bear traces of their iron pins and springs on their backs (LIN-0D8085).

It is useful to consider these two low melting point metals together as they share some properties, and were sometimes combined to form alloys. Tin is an attractive, clean metal often used where it comes into contact with food. Lead, on the other hand, is highly poisonous and ugly. Its only virtue is that, with a melting point of 327ºC, it is easily cast to form intricate shapes and, of course, that it gives a belting good signal on a metal detector! However, only when I started to research this article did I appreciate the importance of both lead and tin, and the many things for which they were used.


As we saw in another article, tin is a vital ingredient of bronze. Without it, copper is a soft, weak metal of limited use but combined with 10% tin we get bronze, an alloy on which civilisations were built. However, the story of tin doesn’t end with the Bronze Age. Bronze was still used in the Iron Age and tin continued to be important – particularly for the British Isles as between AD300 (when the Spanish mines failed) and 1300, Devon and Cornwall were Europe’s main source of tin. Forty-two tin ingots were found on the wreck of a Roman ship found at Bigbury Bay, Devon, in 1991.

Tin is not difficult to extract from its ore and it was cast into ingots for transportation. Tin has some useful features as well: molten tin has excellent “wetting” properties allowing it to be applied to iron and copper alloy objects to give an attractive “silvery” surface that resists corrosion and, importantly, doesn’t taint any food it comes into contact with. “Tin” cans – actually tin-plated steel – remain important today. A curious and useless feature of tin is its “creak”: if a bar of pure tin is bent, it will give a creaking sound.

3: A lead alloy pencil of probably Post Medieval date (AD1500-1800). This example is of particular interest because it is contained within the remains of a bone box. We don’t really know how lead pencils were used but lead will make a mark on light coloured surfaces (SWYOR-CE18D5). 4: There was a fashion for lead jewellery in the Late Anglo-Saxon period and we often see lead strap ends and brooches. This strap end is decorated in “Winchester style” (WMID-53D814). 5: The Vikings set pieces of fine metalwork into blocks of lead for use as weights. This weight contains a piece of enamel-decorated Irish metalwork, but coins were sometimes used (NMGW-07268F). 6: Roman lead ingot with the Imperial inscription IMP DVOR AVG ANTONINI ET VERI ARMENIIACORVM, allowing it to be dated to the period when Marcus Aurelius and Lucius Verus ruled as co-emperors (AD161-9). Its weight is 19.3kg which is much less than the 170 pound standard and it looks like the mould was only partially filled (SOM-23F798).


The other great use of tin was as pewter, an alloy that with its low melting point of 170-230ºC, is easy to cast using clay, stone or even wooden moulds. Stone moulds for casting pewter plates and bowls are known from Roman Britain and medieval stone moulds for casting tokens, badges and other small objects also survive. On leaving the mould the rough castings could be finished on a lathe and component parts readily soldered together to form complex and well-finished objects.

Pewter was much used to make tableware and guild regulations show two different alloys were used in the medieval period: “fine metal” was tin with 1-3% copper, and “lay metal” was tin with lead. Fine metal was harder and more expensive than lay metal, and English pewter had a high reputation all over Europe, protected by the Pewterers’ Guild which looked out for dodgy dealing – that is, lay metal being sold as fine.

7: These lead or pewter objects can present a problem but once you know they are pencil sharpeners, all is clear! (IOW-1577F3). 8: While lead was used in alloys during the later Bronze Age, we don’t get many lead objects from this period. This looped palstave is one of the few examples. We don’t know its function but it was found in the Derbyshire Peak District, a major centre for lead mining (DENO-A24823). 9: A complete cast and stamped lead cloth seal of 17th century date. This is an alnage seal and was fixed to a bolt of cloth to certify its size and quality (IOW-5A65C5). 10: The sling was a highly effective weapon for hurling stones. The Romans used lead bullets like this one, which rendered the sling deadly (BH-27A5B4).

There was a theory that the use of leaded pewter caused the end of Roman Britain. In Britain the Romans made great use of pewter and, it has been suggested that, while the aristocracy ate of silver and the poor off pottery, the middle classes, who ran the whole show, used pewter which, with its high lead content, caused them neurological issues. However, so far as I’m aware, analysis of late Roman bones has revealed no concentration of lead.

Pewter also has its own “catastrophe theory”: that Napoleon’s army was destroyed by their pewter buttons. Tin turns to dust when frozen and while on campaign in Russia the soldiers allegedly suffered an unfortunate wardrobe malfunction. There is sadly no evidence for this story!


In Britain, lead ore occurs in the limestone districts of the Derbyshire Peak District, the Mendips and the borders of Northumberland and Durham. The main ore was galena (lead sulphide) which is easily recognised as it is black, shiny and very heavy. Most early lead mining was carried out by following rakes, or vertical seams of ore, down into the rock. It was only later that proper mines were introduced.

Prospecting for lead and tin was of great importance and miners were allowed to dig anywhere they liked, only avoiding churchyards, gardens, orchards and the highway. This led to conflict with landowners objecting to having their property covered by holes and spoil heaps. The miners had their own courts: the Stannary Courts and Parliament in the South West, and the Bar Moot Court in the Peak District. 

11: Ampullae were small lead bottles which were filled with water at the shrine of a saint so that pilgrims could take home some holy water. These thin sectioned objects were probably made by “slush casting” where the lead or pewter was poured into the mould then immediately poured out to leave a thin shell (LON-1C0F88). 12: This is a lead seal matrix used to seal and confirm documents. It is doubly interesting because the inscription reads: S IVLIANE LE PLVMIR (Seal of Juliana the Plumber) showing that it both belonged to a woman and that she was a plumber (HAMP3151). 13: This medieval spindle whorl acted as a fly-wheel on a drop-spindle which kept it turning to spin the thread. These aren’t uncommon and the PAS has recorded more than 2000 of them, mostly from Norfolk, Lincolnshire and East Yorkshire. They are much less common in the southern counties (FAKL-64A838).

Like tin, lead is easily smelted from its ore which , along with wood to act as a fuel, was simply piled into a bole. This was a shallow hollow on a hillside where the wind provided a natural draft. Around it was a low wall with a passage facing the prevailing wind. After a couple of days, the fire had died down and the lead had either run out of the bole or was left as a lump at its base. While simple, the process was inefficient and the slag was later re-smelted to extract further lead.

Being soft and malleable, lead can be beaten into complex shapes and welds made with a hot iron. It’s also very easy to cast and it is possible to melt it on a bonfire. When I was a boy we used to melt lead in the woods and cast it into any available shape, which might explain the strange lead objects constantly found by detectorists. I have seen lead that has been cast into clay pipe bowls, scallop shells or anything that can be pushed into the earth to form a mould. 

Lead first appears in Britain during the Late Bronze Age when it was added to the copper/tin alloy. We don’t know why this was done but it may have been to make the more valuable metals go further. Some Bronze Age objects have been found to be of pure lead and would have been of little use.

A few pieces of lead have been found on Iron Age sites but things only really get going with the Roman Conquest. We have lead ingots with inscriptions dating them to AD49 (the Romans weren’t wasting time!), whilst the latest dated ingot , bearing the names of Antoninus and Verus, is AD163-169. Roman lead ingots usually weigh around 170lbs – someone pointed out that this this is a weight that it is possible to move but not possible to run away with so making theft difficult. Unlike the rectangular Roman lead ingots, those of the medieval and post-medieval periods are boat-shaped.

14: Strange lead objects like this are found on Viking sites and we think that they are gaming pieces used in “Hnafetafl”, a popular board game (NLM-7ABE36). 15: Trade weights like this one were in use over a long period of time, making them difficult to date. This one bead three lions (WMID-C4D71E). 16: A lead cruciform brooch. We have seen a number of lead cruciform brooches but so far none have been found in graves suggesting that, unlike the Late Saxon disc brooches, they were not actually worn (SWYOR-B40A88). 17: A Late Medieval disc weight, again very difficult to date (SF-847D12). 18: A stone mould for casting pewter tokens. Stone was an ideal material from which to make moulds for casting low melting point alloys (LON-E0BD25). 19: Pot repair used to fill a hole in a Roman “Severn Valley ware” vessel, scraps of which survive in the groove. many Anglo-Saxon urns had holes carefull chipped in their sides which were then filled with lead plugs (GLO-CD15F5).

Much lead was used in building and plumbing – the Romans were famed for their sanitation and the rooves of medieval churches and better buildings were covered in sheet lead. This was cast on an open bed of sand to produce sheets about 4mm thick. 

In the medieval period, lead was much used in the preparation of food and brewing, although it was well-known that the metal was poisonous. Lead was also used to make coffins, and later the gun shot used to put people in them.

The images included here give some idea of the wide range of lead objects recorded by the PAS. Unfortunately, we aren’t usually able to distinguish between lead, tin and pewter.