Basalt

basalt, a dark-coloured, fine-grained igneous rock (see geology) dominated by the two minerals feldspar and pyroxene, though they are usually too fine to be discernible. They weather to provide a good range of potential nutrients. Dark rocks such as basalt are often said to reradiate warmth at night, but Pogue’s study in the Columbia Valley in washington and oregon states suggests that the thermal effects operate chiefly during the day.

Basalt is almost always found in association with volcanic materials such as tuff. In addition to the locations mentioned for them, basalt occurs in Victoria (e.g. King Valley and Macedon Ranges) and the hunter valley in Australia, the Galilee region of israel (including the Golan Heights), and it dominates vineyards in parts of hungary such as Tapolca near Lake Balaton, and Somlo Hill.