Liquid-filled rocks form when minerals trap fluids, but depending on their composition they can either be classed as enhydros, enhydro agates, or fluid inclusions. An enhydro is a hollow nodule that ...

Geodes are hollow rock formations often with quartz crystals ... More information: Fiorella Arduin-Rode et al, World-class amethyst-agate geodes from Los Catalanes, Northern Uruguay: genetic ...

Rockhounding is the recreational study and collection of rocks, gems, minerals or fossils, such as fossilized remains of terrestrial vegetation known as petrified wood or geodes ... Find jasper, moqui ...