RHH's photos with the keyword: sapphire pool

This is Sapphire Pool in Yellowstone's Biscuit Basin. Its blue color indicates its scalding temperature and it is one of the main features of Biscuit Basin. After the Hebgen Lake earthquake of 1959 it became a geyser for a number of years but has since quieted down and returned to its present state.

This is Sapphire Pool in Yellowstone's Biscuit Basin. Its clear blue color might be inviting but it is scalding hot.

This is Sapphire Pool in Yellowstone's Biscuit Basin, its clear blue color an indicator of its scalding temperature.

I believe I have the name of this feature correct. It is one of the hot pools found in many of the geyser basins and here again the color is determined by the algae and thermophilic bacteria that live in the hot water. In this case the blue color indicates that this is very hot, around 160 degrees fahrenheit, with only microscopic thermophiles living in the water.