Ictis

Ictis, or Iktin, is or was an island described as a tin trading centre in the Bibliotheca historica of the Sicilian-Greek historian Diodorus Siculus, writing in the first century BC.

While Ictis is widely accepted to have been an island somewhere off the southern coast of what is now England, scholars continue to debate its precise location. Candidates include St Michael's Mount and Looe Island off the coast of Cornwall, the Mount Batten peninsula in Devon, and the Isle of Wight further to the east.

Diodorus Siculus, who flourished between about 60 and about 30 BC, is supposed to have relied for his account of the geography of Britain on a lost work of Pytheas, a Greek geographer from Massalia who made a voyage around the coast of Britain near the end of the fourth century BC, searching for the source of amber. The record of the voyage of Pytheas was lost in antiquity but was known to some later writers, including Timaeus, Posidonius and Pliny the Elder. Their work is contradictory, but from it deductions can be made about what was reported by Pytheas. No other sources concerning the tin trade in the ancient world are known.

Diodorus gives an account that is generally supposed to be a description of the working of Cornish tin at about the time of the voyage of Pytheas. He says:

The inhabitants of that part of Britain which is called Belerion are very fond of strangers and from their intercourse with foreign merchants are civilized in their manner of life. They prepare the tin, working very carefully the earth in which it is produced. The ground is rocky but it contains earthy veins, the produce of which is ground down, smelted and purified. They beat the metal into masses shaped like knuckle-bones and carry it off to a certain island off Britain called Iktis. During the ebb of the tide the intervening space is left dry and they carry over to the island the tin in abundance in their wagons ... Here then the merchants buy the tin from the natives and carry it over to Gaul, and after travelling overland for about thirty days, they finally bring their loads on horses to the mouth of the Rhone.

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