Munro mine

The Munro Mine refers to historic chrysotile asbestos mining operations in Munro Township, in the Timmins–Matheson region of northeastern Ontario, Canada. The deposit lies within an ultramafic (serpentinized peridotite) body of the Abitibi greenstone belt and produced chrysotile fibers along with associated serpentine and trace amphibole minerals during the 20th century.

Origin

The mine takes its name from Munro Township, an Ontario survey township named in the 19th century. Chrysotile occurrences in the township were investigated from the early 1900s, with intermittent extraction and exploration tied to the broader Canadian asbestos industry centered in Quebec and Ontario.

Significance in Asbestos Context

For patients whose exposure may trace back to Canadian chrysotile, the Munro deposit matters because fiber provenance can help connect a specific product or workplace to a specific ore source. Ultramafic chrysotile deposits like Munro typically contain not only chrysotile but also trace tremolite or other amphibole contaminants, which is important because amphibole content is heavily weighted in causation analyses for mesothelioma. If an expert performs fiber-burden analysis on lung or lymph node tissue, the mineral signature can sometimes be compared against known source-deposit profiles, including Ontario chrysotile, to support or refute a particular exposure history.

Example Sentence

The plaintiff's geological expert noted that the insulation product at issue contained Canadian chrysotile potentially sourced from Ontario operations such as the Munro mine, where tremolite contamination has been documented.

Related Terms

Chrysotile, Tremolite Contamination, Serpentinite, Provenance Analysis, Fiber Burden Analysis, Abitibi Greenstone Belt

Notes

• If you worked with Canadian-sourced asbestos products, ask your legal team to investigate supply chains back to specific mines, not just to "Canadian chrysotile" generically.
• Preserve any product packaging, shipping records, purchase orders, or MSDS sheets that identify the supplier or country of origin of the asbestos used.
• Ask whether fiber-burden analysis of tissue samples is appropriate in your case; mineralogical fingerprints can sometimes link disease to a specific deposit type.
• This term is most relevant in mesothelioma cases where defendants argue chrysotile-only exposure; documenting amphibole contamination at the source deposit can be pivotal.