Coral Spring in Norris Geyser Basin discharging high SiO2 water that ponds and cools enough to polymerize to light-scattering colloidal SiO2 with characteristic opalescent- blue color. Yellowstone National Park, Wyoming. 1959.

Album caption: Wyo - Y.S.N.P. Index card: Coral Spring, discharging high SiO2 water that ponds and cools enough to polymerize to light-scattering colloidal SiO2 with characteristic opalescent- blue color. Note thin sinter crusts deposited at water level and flowline trends (center). Piece of wood in the left foreground is about 0.3 m long. Norris Geyser Basin. Yellowstone National Park, Wyoming. September 1959. Published as Figure 9 in U.S. Geological Survey. Professional Paper 1456. 1988.