EduR23 Vesicular Basalt

3D Model

84×76×38mm

Quaternary (<2.6Ma)

Vesuvius, Italy

Basalt is an igneous rock with the same silica-poor composition as gabbro, evidenced by its dark colour as many silica-poor minerals are darker coloured. Such rocks are typically generated from melting of the mantle. It has tiny crystals that are not visible to the naked eye as it often forms when magma is erupted at the surface, meaning it cools quickly and crystals do not have time to grow. As magma rises, the pressure decreases, and the gas bubbles within expand, which is what causes the bubbles, or vesicles, in this basalt. Only igneous rocks can have these vesicles.

Mount Vesuvius, where this basalt was collected, is one of the most dangerous volcanoes in the world because over 600000 people live in the danger zone of an eruption. It erupts relatively frequently, with a powerful one famously destroying the Roman city of Pompeii killing over a thousand people, and is the only volcano on mainland Europe to have erupted in the last hundred years in 1944.