Thundereggs look like regular rocks from the outside, but contain intricate and colorful mineral patterns inside — often made ...

Large crystals found in geodes and other rocks are relatively rare. Pink ChalcedonyA pink chalcedony shows off its beauty. Chalcedonies include many types of cryptocrystalline quartz gems and ...

Liquid-filled rocks form when minerals trap fluids, but depending on their composition they can either be classed as enhydros ...