* Cleavage refers to the tendency of a mineral to break along specific planes of weakness within its crystal structure. This is a property inherent to the mineral itself.
* Geodes are not a single mineral, but rather a hollow rock structure lined with crystals. The crystals within the geode may exhibit cleavage, but the geode itself doesn't.
Instead of cleavage, geodes are described by their:
* Fracture: How the geode breaks when subjected to stress. Geodes often have a conchoidal fracture, meaning they break in curved, shell-like shapes.
* Structure: The hollow cavity within the geode is a key characteristic, often lined with crystals that have grown inward from the walls.
Think of it this way: A geode is like a little treasure box. The box itself (the outer rock) might break in a certain way (its fracture), but the treasure inside (the crystals) might have its own way of breaking (cleavage).
