Stones do not float in water. This is a truism. But there is hardly a rule without exception. In fact, some volcanic eruptions produce a very porous type of rock with a density so low that it does ...

Over the last year, we’ve seen lava fountains at volcanoes like Kīlauea in Hawai’i, Etna in Italy, and Svartsengi near Reykjavík in Iceland. These fountains have sometimes reached heights over 1,000 ...

The small town of Escolásticas, built on ancient volcanic stone, carves a ragged path through a high desert hillside in Central Mexico. Three hours northwest of Mexico City, this community of ...

A metate is a grinding stone common to Mesoamerican cultures, past and present. Corn and other grains are ground against the volcanic stone with another stone held in the hand called a manos.