Watch a video of this specimen by following the Vimeo link below: https://vimeo.com/1176941215/b43b82950a A large and impressive tourmaline specimen from Stak Nala, Pakistan, featuring deep blue color zoning. The distinctive color is most probably due to human-induced irradiation treatment. Despite this enhancement, the specimen offers excellent scale and aesthetic appeal as a tourmaline-muscovite-quartz combination piece Ex coll. Bac. Jean-Pierre Bac was a highly active regional field prospector in the departments of Cantal, Aveyron, and Lot from the 1970s through the 2010s. He became a specialist of Curebourse and Enguialès, having developed a close relationship with the family who owned the latter mine. Several specimens from his Curebourse collection were illustrated and published in Le Règne Minéral (1999, issue 29). He also made several remarkable and unusual discoveries in a quarry near Miécaze. Another part of his collection consisted of carefully selected international specimens acquired from French mineral dealers during that period.