Don Komarechka, a Canadian photographer and author of the book Sky Crystals: Unraveling the Mysteries of Snowflakes, captures absolutely striking macro images of individual snowflakes that contain colorful patterns inside. These colors and patterns can be caused by malformations as the flake develops, a change in thickness, moisture and even external forces like wind. Komarechka explains this incredible natural phenomenon in a blog post on PetaPixel.
At first, this was a little hard to believe. How could this be possible? Having seen thousands of snowflakes of all varieties, where has this mysterious color come from? The solution is simple, though the conditions required are rare: thin film interference. As a snowflake grows it often creates a cavity or bubble inside of it where the inner side of the crystal grows slower than the top and bottom edge. This forces the layers of ice on either side of the bubble to be incredibly thin, so much so that light will interfere with itself.