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Some Arabic and Persian accounts of the export of tin from Cornwall to Egypt and Iran in the thirteenth and fourteenth centuries — new brief post by me :) https://www.caitlingreen.org/2020/11/arabic-and-persian-accounts-of-cornish-tin-trade.html
Two accounts, taken together, suggest that tin from southwestern England (i.e. Cornwall and Devon) was exported via southern France to both Egypt and ultimately Iran in c.1300, with it being used by potters in the latter area to make tin-opacified ceramic glazes (pic=mina'i bowl)
The first was written c.1321 by Abū l-Fidāʾ and refers to the earlier work of Saʿīd al-Maghribī (d. 1286); it talks about tin from England being taken to southern France and then by ship to Egypt...
The second is from a treatise on ceramics by Abū l-Qāsim Qāshānī of Kashan, Iran, written in c. 1300–01, which talks about the importation of tin to Iran from Western Europe, or Farangistān, before discussing how the tin was used to make white and turquoise ceramic glazes...
A mina'i ware bowl showing the Sasanian hero Bahram Gur on a camel with Azadeh; overglaze enamels painted over tin-opacified glaze, late 12th-/early 13th-century Iran: https://www.metmuseum.org/art/collection/search/451389
A 13th-century shaped tile with painted lustre, probably made Kashan, Iran, and now in the Royal Cornwall Museum.
A mina'i ware jug with seated figures and sketches, made in Central Iran in the late 12th or early 13th century, earthenware with polychrome enamels and gold over a turquoise glaze; now in Cincinnati Art Museum: https://commons.m.wikimedia.org/wiki/File:Jug_with_seated_figures_and_sketches,_Mina%27i_ware,_Central_Iran,_Seljuk_period,_late_12th_or_early_13th_century,_earthenware_with_polychrome_enamels_and_gold_over_turquoise_glaze_-_Cincinnati_Art_Museum_-_DSC04014.JPG
One interesting question is whether Cornish tin was used from the first appearance of tin-opacified ceramic glazes in 8th-century Egypt? Unfortunately no earlier textual refs, but it is worth noting that tin was known as 'the Brittanic metal' only a century earlier in Egypt...
Also of interest is the wider use of tin-opacified ceramic glazes; e.g. has been argued that Cornish tin was exported in medieval/early modern eras to Spain & Italy for this purpose, see https://tandfonline.com/doi/abs/10.1080/09503110.2011.617061 (pic: 14thC ceramic dish with tin glaze, made Paterna, eastern Spain)
A tin-glazed jug (c.1600) and a tin-glazed charger with lustre decoration (mid-16th century) from Spain, both in the Royal Cornwall Museum.
