by Hilary Whitelock

A bundle of tin straws was one of the items which fascinated me at the St Just Mining and Minerals Museum, during the excellent DTRG visit to the Botallack area in May. These rather contorted sticks of tin are ca 50 – 55cm long, roughly D-shaped in cross-section and ca 9mm diameter. One end tends to be slightly thinner. They would originally have looked quite different, due to being submerged for well over 100 years and in conditions where encrustation by the rare mineral abhurite can occur. The museum was informed by Wheal Jane Laboratory (WJL), who loaned these straws, that they came from the wreck of SS Cheerful and were purer at one end (about 99.8% versus ca 90% tin) but otherwise had little further information.

Close-up of Tin Straws. Photo by author.

There are a few references to tin straws on the internet, relating primarily to recoveries of cargo from the wrecks of SS Cheerful, which sank off St Ives in 1885 and SS Liverpool, sunk off Anglesey in 1883. The straws were apparently stacked in barrels and accompanied cargoes of tin ingots. So what were they for and how were they made?

As to their uses, there is an interesting discussion from 2014 on Mindat.org, summarised as follows. The discussion initiator suggested the prevalent belief was that tin straws were used for soldering, though one respondent was doubtful, as the purity was too high (99% tin quoted) and there was no lead content, a former component of solder. Alternatively, tin straws might have been made as samples, but have no smelter’s mark, unlike ingots and large numbers were packed together in barrels. They could also have been ‘runners’, strips inadvertently cast in channels into or between moulds for ingots. However, runners tend to be much shorter and wider (so the molten metal can flow freely and to minimise cooling) and surely they would have been melted and recast on site.

Tin straws could support the need for much smaller quantities of tin than the 26 lb or 52 lb ingots also carried on SS Cheerful, e.g. for metallurgists, sculptors, or coating the insides of copper culinary vessels and plating pewter. Tin was evidently used for making or plating cheap jewellery in the nineteenth century and could be hard to distinguish from silver, apart from lacking a hallmark. An article about Iron Age tin mining in the Transvaal reported that ‘rod ingots’ of very similar dimensions to the tin straws described above could be easily cut into pieces and used for making rings and bangles (Friede and Steele, 1976).

Interestingly, although SS Cheerful’s final destination was Liverpool, she was due to put in to Swansea with cargo for a tin plating works. If the straws were purer than ingots, their use for the final layer of tin plating is worth considering.

Regarding the manufacturing process, the discussion cites the Penlee House and Gallery, Penzance whose website had a photograph captioned: ‘Marble slab with many thin vertical grooves cut into it. It came from the Tin Smelting House at Chyandour and was used to make ‘streaky tin’… ’ (which the museum thought synonymous with tin straws). However, the description goes on to say that ‘Molten metal was run through these channels ….. into flat metal moulds’ so even if thin strips were made during the casting, this was not the final mould. The ‘closed’ ends of the grooves would not facilitate this process, so the caption is puzzling. As the slab was later confirmed by the Museum as only 30 x 70 cm (and actually of granite), any tin strips made would also have been shorter than the tin straws found in wrecks.

Possible mould for Tin Straws: Carved granite slab 70cm X 30cm – located at Penlee House

The mindat.org discussion aired a wide range of ideas as to why tin straws were made. Reflecting on this, the need for tin in small quantities in the manufacture of small objects seems one of the most plausible uses. Small amounts of metal could be snipped off a thin tin straw and then perhaps beaten into shape. A report on ‘Native Tin Smelting in Nigeria’ in 1918 by Roberts (1924) described tin straws of diameter only 0.1 in (2.5 mm) being made there and used for solder, coating the insides of brass utensils and for bracelets, rings or other ornaments.

Jenkin (1948) remarked that smuggling tin has gone on from early times and tin straws would have been easy to conceal. He tells that around 1700, smelted tin ‘was run off into wooden moulds and in the form of small portable pieces known as “pocket tin”, was sold to seafaring men and wandering pewterers’. ‘Run’ tin may well have been straw-shaped. However, straws from a ship’s cargo, stacked in quantity, are unlikely to have been contraband.

An interesting advantage of forming tin into straws, proposed by Clifford Rice of WJL, is that the very process of ‘running’ molten tin into grooved wooden moulds has the effect of producing very pure tin at the furthest (thickest and rounded) end, as impurities tend to remain at the molten tin’s point of contact with the mould as it cools. WJL still use this technique for refining tin today. If the straws on SS Cheerful were destined for the Swansea tin plating works, Clifford suggested that tin from the less pure end of the straws may have been used for the first dip and the purest tin for the final dip.

photo of fibers from barrel which contained tin straws
Fibers from barrel that held Tin Straws. Photo by author.

Were tin straws a particularly local product of west Cornwall or were such objects ever made from Dartmoor tin? A different bundle of straws from the wreck of SS Cheerful were described at auction as coming from Treloweth, Mellanear and Carvedras tin smelters in Cornwall. Also on SS Cheerful, accompanying the bundle of straws held by Clifford Rice, were other relics: some wood and possibly hemp fibres, likely to have come from a barrel and string and a metal ‘mark’, or plate, which would have been attached to a barrel of straws, bearing the name Tamar Union Tin Smelting Works. This worked from 1849 to 1896 at Weir Quay in Devon and steamships were known to pick up cargo from several different south-west ports. So maybe tin straws were once made much more widely. However, it is likely that these unusual objects will retain much of their mystery: They were made to be used and only owe their survival to shipwrecks.

References:
Mindat.org (https://www.mindat.org/mesg-326688.html#326768).
Penlee House and Gallery, Penzance. Website: https://penleehouse.org.uk/object/pezph-1991-586/
Friede, H.M. and Steele, H.R. (1976) Tin mining and smelting in the Transvaal during the Iron Age. Journal of the South African Institute of Mining and Metallurgy July 1976, p466.
Roberts, A. Trevor (1924) Native Tin Smelting in Nigeria. Mining magazine Vol. XXX pp. 339 – 344.

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