It's very easy to make a glow in the dark crystal geode. The 'rock' is a natural mineral (eggshell). You can use one of several common household chemicals to grow the crystals. The glow comes from paint, which you can get from a craft store. Glow in the Dark Geode Materials eggs glow in the dark paint (I used GlowAway™ washable glowing paint) very hot water (I used my coffee maker) borax, alum, epsom salts, sugar, salt, or use another crystal recipe food coloring (optional -- I used neon green coloring) Prepare the Glowing 'Geode' There are two ways to crack your eggs. You can carefully crack the top of the egg by tapping it on a countertop. This will give you a deep geode with a smaller opening. Alternatively, you can crack the equator of the egg or carefully cut it with a knife. This will give you a geode you can open and put back together. Dump the egg or make scrambled eggs or whatever. Rinse out the inside of the eggshell with water. Pee...