[2] MCI purchased Luganure Mine, County Wicklow, and worked it for 66 years.

[3] The company also prospected at the copper mine at Ballydehob, County Cork in the 1850s.

It leased an iron ore mine at the Glen of Imaal in 1859, but this endeavour was not successful.

[5] The MCI operated at a loss at a number of their mines, including the Mardyke, during the Great Famine.

[5] The mining industry in Ireland grew until the 1860s, when the events surrounding the American Civil War led to the collapse in mineral prices and the Irish mining industry.