In general, mineral particles are small, having formed within confined areas such as lava flows or between grains of sediments. Large crystals found in geodes and other rocks are relatively rare.

They learned the volcanic rock in the lava tubes created a protective environment that helped shield the minerals and organic compounds from weathering, ultimately preserving the minerals as ...

Skull Hill is a type of “float” rock — one that likely originated elsewhere and was transported to its current location.

The process that creates these stone forests is called permineralization, where minerals ... Exploring a lava bed is like stepping onto another planet, with sharp rocks and curious shapes formed ...