While working on this painting I saw am image of blue ice appear and reflected on the Alaska trip a good friend of mine recently took.
She sent photos and video of the amazing sights, including blue ice glaciers. I was in awe!
Blue ice occurs when snow falls on a glacier, is compressed, and becomes part of the glacier. Air bubbles are squeezed out and the ice crystals enlarge and become more dense.
That super-dense ice absorbs every other color of the spectrum except blue, making the ice appear blue to the human eye.
The denser the ice, the bluer it appears.
So COOL. (Pun intended!)
Here are some resources if you want to know more: