What is the solid form of lava that is frothy when it reaches the surface called?

The solid form of lava that is frothy when it reaches the surface is called pumice. Pumice is a light, porous volcanic rock formed when lava cools rapidly and gas bubbles are trapped within it, resulting in its characteristic frothy texture. Due to its low density, pumice can float on water and is often used in various applications, including abrasives and lightweight construction materials.