These attractive basalt columns can be used as decorative pieces as well as fountains. A selection of varying sizes allows you to create the set you desire.
Basalt is an extrusive or intrusive rock that makes up most of the world's oceanic crust. Basalt is fine-grained so that the individual minerals are not visible, but they include pyroxene, feldspar and olivine. Basalt can show bubbles made by carbon dioxide and water vapor that came out of the molten rock as it approached the surface. During its long period of storage beneath the volcano, green grains of olivine came out of solution as well. So the bubbles, or vesicles, and the grains, or phenocrysts, represent two different events in the history of this stone. A volcanic (igneous) stone that has been used in architecture for centuries.