Emerald Pool, Black Sand Basin, Yellowstone

Not sure if this is Emerald Pool or Rainbow Pool! I've seen a lot of photos that name it as Rainbow Pool, but just found others that name it Emerald, which makes more sense to me. Continued research is needed! Think that maybe Emerald is the correct one.

"Temperature 154.6°F Dimensions 27x38 feet. Depth 25 feet. Named for its emerald green color, it is one of the main attractions at Black Sand Basin. The color is the result of lower temperatures which have allowed yellow bacteria and algae to grow on the lining of the pool. The clear water of the pool reflects the blues but absorbs the other hues of the color spectrum. The combination of blue and yellow then produces green. Objects thrown into the pool and natural debris have caused a further decrease in temperature, resulting in a change of bacteria and algae growth and thus a change of color. The edge of the pool is now orange and brown. If the temperature continues to decrease, the pool may lose its emerald color."

www.yellowstonenationalpark.com/blacksand.htm