Evaporation ponds change color at the potash mine in Moab, Utah. The facility produces muriate of potash, a potassium‐containing salt that is a major component in fertilizers. The salt is pumped to the surface from underground brines and dried in these massive solar ponds. As the water evaporates over a span of 300 days, the salts crystallize out. The variation of color occurs because the water is dyed a deep blue (darker water absorbs more sunlight and heat, thereby reducing the amount of time