Crystal Geode

Grow a beautiful, colorful crystal geode — a hollow rock with crystals inside it — by first molding a plaster shell and then filling it with a crystal-forming solution. Learn about geological crystal formations.

Thames and Kosmos makes great kits and the manuals are so full of great science information.  They are truly a step above other science kits!

Thames & Kosmos was founded in 2001 by a science museum director and her son, who saw the great need and demand for better science education materials — resources for parents and their children that are more engaging, more effective, more relevant, and more fun.