Geodes are small rock cavities lined with crystals or minerals. They form through sedimentation, a process in which particles (solute) are suspended in fluid (solvent) and then accumulate. (Here, the ...

Using a few materials from around the house, you can turn an ordinary egg into a geode. STEP 2: Using warm water, clean the inside of each egg. STEP 3: Place the eggs into the egg carton and let dry.