Hibernia mines

{{short description|Series of iron mines in New Jersey}}

{{Use American English|date=June 2025}}

The Hibernia mines are a series of iron mines in and around Rockaway Township, in Morris County, New Jersey, United States, that were worked from pre-Revolutionary times until 1916. The mines worked a vein extending for more than {{convert|2|mi|km|spell=in}}. Several companies operated mines in the area. An adit was constructed into the Hibernia hill to move ore to the railhead of the Hibernia Railroad. Ore in excess of {{convert|90000|ST|MT}} was shipped in 1879.{{cite book |title=History of Morris County, New Jersey with Illustrations, and Biographical Sketches of Prominent Citizens and Pioneers, 1739-1882 |date=1882 |publisher=W.W. Munsell & Co. |url=http://www.usgenwebsites.org/NJMorris/history/munsellhistory/h-chpt10.htm |access-date=10 December 2020 |chapter=10}}

An exploratory shaft was drilled in the 1950s but was not worked, and the shafts and adit were partly or totally sealed in 1972 and 1989.

After its closure, the mine became the largest bat hibernaculum in New Jersey, with as many 30,000 bats each winter.{{Citation | last = Dutko | first = Rick | title = Conservationists tried to protect the bats at this important New Jersey site many years ago; this summer they finally succeeded… | journal = BATS Magazine | volume = 12 | issue = 3 | pages = 3–5 |date=Fall 1994 | url = http://www.batcon.org/index.php/media-and-info/bats-archives.html?task=viewArticle&magArticleID=665 | accessdate = April 10, 2010}} In 2010, less than 10% that number was found in the mine following an outbreak of white nose syndrome.{{Citation | author-link = Associated Press | title = Fungus kills 90 percent of N.J. bat population, scientists say | newspaper = The Star-Ledger | date = April 3, 2010 | url = http://www.nj.com/news/index.ssf/2010/04/fungus_kills_90_percent_of_nj.html | accessdate = April 10, 2010}}