Zinwaldite

This specimen showcases brilliant, lustrous, silvery micaceous crystals of zinnwaldite, an impressive example for the species. Zinnwaldite, a lithium-rich mica, is known for its shiny, metallic appearance. The specimen originates from the Tanco Mine (Bernic Lake Mine), located on the northwest shore of Bernic Lake, Manitoba, Canada. The Tanco Mine is renowned for being the world's largest producer of caesium, with the largest known deposit of pollucite. Additionally, it holds the largest tantalum reserves in Canada, making it a significant mining site. The pegmatite ore body currently mined was discovered in the late 1920s, and mining operations began in 1929. The mine has seen several closures and reopenings, with its most recent resurgence in 1969 as a tantalum producer. Since 2019, the mine has been owned and operated by Sinomine Resource Group.