Black Sand
(c) 2000 Andrew Alden, licensed to About.com, Inc. (fair use policy)
The waves of the Hawaiian coast quickly turn fresh lava from Kilauea volcano into this black sand, magnified here about 2 times. Normally the sea doesn't have material this fresh to work with—more typical is weathered quartz and feldspar grains delivered by rivers to the coast after a long journey. This black sand is entirely rock fragments. Other black sands are composed of black minerals like ilmenite.
Fossils
Geologic Features and Processes
Glaciers and Ice
Landforms
Minerals
Rocks
Geology and Society
