Why do icebergs often look white or blue?

Icebergs often appear white due to the air bubbles trapped in the ice, which scatter light and give them a bright, reflective appearance. In contrast, icebergs can look blue when they are dense and have fewer air bubbles, allowing them to absorb red wavelengths of light and reflect blue wavelengths. The blue coloration is more pronounced in older, compact ice that has undergone significant melting and refreezing.