Michigan entered the Atlantis gazetteer when Frank Joseph claimed that copper was at the heart of Atlantean wealth. He further maintained that a major source of this copper was the Michigan North Peninsula from where millions of pounds of the metal were extracted. Conventional wisdom has never explained the source of the vast quantities of copper required to feed the needs of the European Bronze Age. Researchers, such as Joseph, are convinced that the abandoned Michigan mines were exploited by pre-Columbian trans-Atlantic mariners, possibly Atlanteans, in order to satisfy the demands of the Mediterranean Bronze industry.
A short paper in the Migration & Diffusion website(d) by Gerard Leduc in 2017, suggests a possible route that may have been used for the exportation of the Michigan copper to the Atlantic Ocean, before heading for the Mediterranean and/or Europe.
Professor Ilias Mariolakos in a 2010 paper(c) supported the idea of Old World miners in Michigan, identifying prehistoric Greeks as participants.
In 1982 an ancient shipwreck was discovered near Uluburun in Turkey. On board were 10 tons of copper ingots whose purity led some conclude that it could only have come from the Michigan mines. J.S. Wakefield has written a paper supporting this view(a), although he does not directly attribute this copper trade to Atlanteans.
However, Gavin Menzies in The Lost Empire of Atlantis claims that Minoan Crete was in fact Atlantis and that the Minoans not only discovered America but were also responsible for the extensive exploitation of the Michigan copper mines.
It must be stated that this idea of the Michigan copper mining being work of Old World traders is hotly disputed by local archaeologists(b).
*(b) http://www.ramtops.co.uk/copper.html (offline) See: Archive 2102*