In Pennsylvania my g-grandfather worked in a coal mine along with his brother-in-law Thomas Lynch, who had brought his family in 1859 from Lancashire in the UK where he also was a miner. At this time the coal fields in this part of Pennsylvania were just being developed and I wonder whether the families decided to go there, to get in on the ground floor.
Have you researched mining linked to migration?
The Mining Heritage Trust of Ireland
There is a mining database project Find Your Mining Ancestors
Mining and Migration
https://www.glensoflead.com *
"As with the Cornish who worked with the Irish in mines across 18th and 19th-century Ireland, Irish mineworkers were also highly mobile, moving from one mining field to another as the fortunes of the industry waxed and waned."
Cornishmen were often the mine-captains.
"Networks of Metalliferous Mining Migration in the Nineteenth Century Transatlantic World"
"Miners in Migration: The case of Nineteenth Century Irish and Irish-American Copper Mines" by Timothy O'Neil. (2001) Irish-American Cultural Institute vol. 36. Project Muse.
https://muse.jhu.edu/article/667014/pdfCornish tin mining declined from 1840s.
Many Irish miners went to Cumberland and Lancashire in North-West England or Yorkshire, Durham and other counties of North-East England and to Scotland. It's possible that some Munster miners may have gone to Welsh mines or to mines in South-West England.
See website Cumbrian Irish. Many lived in the village of Cleator Moor.
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