The mines at Knockmahon were operated by the Mining Company of Ireland (MCI). Bonmahon was the village where the largest part of the workforce lived. The records of MCI are not listed in Hays and do not appear to be in any public repository. I have not found them yet, and have been researching Irish mining history since 1993. The printed half-yearly reports do not contain lists of employees. The only employee lists I have seen for Irish mines are from the Berehaven Mines in County Cork. The person who has done the most work on the Knockmahon mines is Des Cowman -- see his "Life and Work in an Irish Mining Camp c. 1840," Decies 14 (1980);"Survival, Statistics and Structures: Knockmahon Copper Mines, 1850-78," Decies 46 (1992); and "Landlords and Their Minerals c. 1850: Two Waterford Case Studies," Decies 47 (1993) -- among a number of essays he has published. The Mining Heritage Trust of Ireland began a journal last year which may be of interest to many on the list. Bill Mulligan