Santa Catalina Mountains | Pima County, Arizona Thin layers with high concentrations of fine, maroon-colored garnet crystals in Eocene pegmatitic granite near Marshall Gulch in the Santa Catalina Mountains. These are known as garnet “schlieren”. Head of rock hammer for scale. (Photo by Jon Spencer)
Photographer: Jon Spencer
Photo Date: circa 2010
Photo Location Accuracy: Approximately Located
Photo Tags: Santa Catalina Mountains, Summerhaven, Eocene, pegmatitic granite, Marshall Gulch, garnet, schlieren 
