Quarrying in Iowa

The Hanlons, Finnegans and Bradys  all found themselves in Stone City, Jones County, Iowa for the 1870 census.  John Hanlon, my great grandfather, (indexed as John Handlin) was listed as employed at the Stone Quarries with brothers-in-law Peter Finnegan and Andrew Brady.  I had searched for information on the mines at that time and all along, the history was right here in one of the monthly Palimpsests from the Iowa Historical Society.  This one was from May 1957 and contains some great pictures from Stone City:
as well as this little history:
John moved onto farming in Polk and Dallas Counties in Iowa before his death in 1895.  Peter Finnegan, who was married to John's sister Margaret, stayed in Jones County until his death in 1901.  Andrew Brady, brother to John's wife Catharine, died in Jones County in 1879.