Sunrise at Emerald Lake in Yoho National Park, British Columbia, Canada. Mount Burgess is lit up by the sun's early rays. The colour of Canada's lakes is spectacular. As the melt water from a glacier that feeds a lake starts to flow in springtime, it carries glacial silt or rock flour. The silt is created when rocks underneath the surface of the ice are ground during the movement of the glacier. The rock flour is very light and so remains suspended in the lake water for a long time. The blue / green wavelength of sunlight reflect off this rock flour and gives the lakes their spectacular turquoise colour.