Howlite is a super-calming stone and many people use it to relieve stress of all kinds. It makes an excellent antidote to insomnia due to an overactive mind. About Lava Rocks: Basalt and related rock types like andesite and dacite are rocks that form when volcanoes erupt magma (lava) onto the surface of the earth and the magma cools. Lava beads are porous and can even absorb the oil of your choice.