The Tanco Pegmatite at Bernic Lake Manitoba, Canada

Click to increase image sizeClick to decrease image size ACKNOWLEDGMENTSI offer this article as a tribute to Petr Černý, a sorely missed friend and colleague, whose legacy of works on the Tanco pegmatite made it the most thoroughly investigated pegmatite in the world. Without his contributions, this synthesis of the internal evolution of Tanco would not have been possible. I thank Claude Deveau and Aaryn Hutchins, Tantalum Mining Corporation of Canada Ltd., Peter Vanstone and other former personnel there for their support for my visits to the mine. Aaryn Hutchins provided the image for figure 16, and Michael Bainbridge, Carl Francis, and Phil Persson offered other images of minerals from Tanco. William Besse prepared the locality map. Reviewers Carl Francis and Mark Jacobson provided helpful comments to improve the manuscript.Notes* HEAT3D is a finite-element thermal diffusion model available as freeware from KWARE, software by K. Wohletz, available at https://kware-heat3d.software.informer.com/; accessed January 2023.* A copy of the Excel program of Morgan (Citation2016) for the calculation of proportional tourmaline components is available as open source at http://www.minsocam.org/MSA/AmMin/toc/2016/Jan2016_data/Jan2016_data.html.Additional informationNotes on contributorsDavid LondonDr. David London is a professor emeritus of the School of Geosciences at the University of Oklahoma. Granitic pegmatites have been the focus of his research for fifty years.