Blue Sapphire Pool Blue Sapphire Pool

Reaching temperatures in excess of 202 degrees F, the Oriental Blue Sapphire Pool is part of the isolated thermal group known as Biscuit Basin, located in the larger Upper Geyser Basin of Yellowstone National Park in Wyoming. Biscuit-like sinter deposits prominently lined its crater edges in the 1880's. However, an earthquake in 1959 dislodged many of the knobby formations. After the earthquake many large eruptions occurred at two hour intervals and some reached as high as 150 feet. The eruptive forces caused the crater of the oriental blue sapphire pool to double in size but by 1968 the pool ceased to function as a true geyser.

Today, the pool is about 18 ft. by 30 ft. and with an estimated depth of 125 feet. Occasional surges and violent boiling still occur but it remains quietly dormant the majority of time. These pool waters in Yellowstone will boil at around 198 degrees F. The crystal clear water and vividly blue color is true to life in this photo. The blue color is due to the sterile water purity from extreme temperature and the depth of the pool. Surrounding bacteria fields which often create rainbow-like colors are virtually non-existent here due to the temperature.