Black Lava Stone. Black Lava Stone consists of Basalt. More than 90% of all volcanic rock on Earth is basalt Lava is a rock formed from magma erupted from a volcano. Once the stone is cool, it becomes porous and black. Since lava is known for its grounding qualities, it's wonderful for calming the emotions, It has a calming- but intense energy. It's considered to be a stone of rebirth and shedding unneeded layers of emotional attachment and can help you connect with nature. Lava stones are fantastic for stabilizing and grounding the root chakra. In folk remedies, it was also given to soldiers to help them remain calm during battle. .