Deep-ocean pillow basalt main content.

Deep-ocean pillow basalt

Part of Hall of Planet Earth.

Deep-Ocean Pillow Basalt

This sample was dredged from a seafloor spreading center near Japan. The shiny black surface is glass, a product of rapid cooling of lava underwater. The white crystals in the glassy crust are plagioclase, a common mineral in most rocks.

Loaned by the Geological Survey of Japan