Volcanic rock is a type of rock formed from molten LAVA that has cooled and solidified. The crossword solutions for the term volcanic rock include LAVA (4 letters), tufa (4 letters), obsidian (8 letters), BASALT (6 letters), pumice (6 letters), andesite (8 letters), trass (5 letters), tuff (4 letters), and taxite (6 letters). LAVA is molten rock expelled by a volcano during an eruption, while tufa is a type of limestone formed by the precipitation of calcium carbonate in water. Obsidian is a type of igneous rock formed from cooled LAVA, while BASALT is a dark-colored, fine-grained igneous rock. Pumice is a light-colored, porous volcanic rock, and andesite is an intermediate volcanic rock composed of plagioclase and pyroxene minerals. Trass is a type of tuff composed of volcanic ash, while tuff is a type of rock made up of consolidated volcanic ash. Taxite is a type of rock composed of volcanic ash and other materials.