Mcgillite

Mcgillite is a rare, monoclinic, pseudohexagonal mineral of the Pyrosmalite group, with the formula Mn²⁺
₈Si
₆O
₁₅(OH)
₈Cl
₂. It was first approved in 1979, and is named for McGill University.

Mcgillite specimen in the Redpath Museum, McGill University.

Mcgillite is found in the Sullivan Mine, Kimberley, Kootenay district, British Columbia, Canada; the Kyurazawa mine, Tochigi Prefecture, Japan; and at one location in Romania. At the Sullivan mine, it forms as fracture fillings in a manganese-rich portion of quartzite and argillite within a metamorphosed lead-zinc deposit. It is pink in color.

References

• Handbook of Mineralogy
• DakotaMatrix entry
• Mindat.org entry