Specimen Number28-6-020Commentsfrom Crowe research collection; J. Rosdeutscher MS materialsIn Teaching CollectionNoMineral(s)kaolinitepyritequartzField Notesheavily altered phonolite w/ kao+py veinRock Namealtered phonoliteDistrictCripple CreekMineGrassy ValleyGeo-LocationDDHGVC-2 110ft.Deposit TypeDiatremeGeo-Coords[1] Reference MaterialRosdeutscher, J.A., 1999, Geology and Stable Isotope Geochemistry of the Grassy Valley Au Deposit, Cripple Creek District, Colorado: Evidence for Magmatic Fluids; University of Georgia MS thesis, 76 p.
28-6-020: altered phonolite - Cripple Creek District - Grassy Valley Mine. Franklin College Collections, accessed 10/05/2026, https://digitalcollections.franklin.uga.edu/nodes/view/35912