It was discovered in January, 1953[1] and entered production in April, 1964.

The Brunswick #12 orebody is the largest deposit in the Bathurst area and was one of the largest underground zinc mines in the world[1] well into the late 1990s.

The mine was officially closed at the end of April, 2013.

[2] The supergiant Brunswick #12 deposit is a volcanogenic massive sulfide (VMS) deposit rich in lead, zinc, and copper.

Currently the copper-rich portion of the deposit has not been mined.