Grand Prismatic Spring - Yellowstone NP
Grand Prismatic Spring is the largest hot spring in Yellowstone and the 3rd largest in the world; the first two are in New Zealand. Grand Prismatic discharges an estimated 560 gallons of water per minute.
This spring begins with a deep blue center followed a pale blue. Green algae forms beyond the shallow edge (which can be more easily seen by enlarging the image). Outside the scalloped rim a band of yellow fades into orange followed by red which marks the outer border. The entire spring is often shrouded in steam which actually reflects the beautiful colors.