Beached pieces of ice along the Jokulsarlon black sand beach at dawn. The crystal blue clear ice comes from a glacier where it has been trapped for thousands of years under very high pressure giving it the intense color. Blue ice occurs when snow falls on a glacier, is compressed, and becomes part of the glacier. Air bubbles are squeezed out and ice crystals enlarge, making the ice appear blue. After the ice breaks off, the large chunks get pulled out to sea at low tide. They get broken up in the strong surf and then washed up onto the sand.