Let's analyse the chemical composition. If it's is made of fused quartz, it's likely to be a fulgurite. If it's made of calcium carbonate, it's likely to be a

Let's analyse the chemical composition. If it's is made of fused quartz, it's likely to be a fulgurite. If it's made of calcium carbonate, it's likely to be a coral. If it's made of something else, that's even more exciting!