Morning Reflections in Moraine Lake, Banff National Park, Canada.  The lake really is emerald-colored like this. It comes from **rock flour** which consists of fine-grained, silt-sized particles of rock from glacial erosion.  They suspend in the water and the refraction of light off of them causes the amazing color.

Morning Reflections in Moraine Lake
Morning Reflections in Moraine Lake, Banff National Park, Canada. The lake really is emerald-colored like this. It comes from **rock flour** which consists of fine-grained, silt-sized particles of rock from glacial erosion. They suspend in the water and the refraction of light off of them causes the amazing color.