These crystals are produced in molten rock as it travels from deep inside Earth to the surface. With increasingly sophisticated scientific methods, we can extract a secret history of volcanoes ...

That’s par for the course on the red planet, but there was something very different about this rock. It had a surprise inside: pure sulfur crystals, something never before seen on Mars.

About 400 kilometres northwest of Sydney, just south of Dubbo, lies a large and interesting body of rock formed around 215 ...