I think it's more because air bubbles are squeezed out as the glacier moves, making it clearer than fridge ice which usually contains many air bubbles. http://

I think it's more because air bubbles are squeezed out as the glacier moves, making it clearer than fridge ice which usually contains many air bubbles. http://en.wikipedia.org/wiki/Blue_ice_(glacial) http://en.wikipedia.org/wiki/Blue_ice_(glacial)