Amazing Science Surprises: Magic Stone-prospector Pete&rsquo;s Fortune in Gems, Science Principles explored in this kit: chemistry, applied science This is an amazing and fun toy for kids of all ages from 4 to 84. Grandparents/parents enjoy quality time when the kids with this toy. First read the short story on the back cover of how Pete made his millions in gem then came across a leprechaun to hide his fortune in these magic ugly rocks. Pete hated the banks and didn't trust them back in the 1800's either. Then follow the simple directions to uncover Pete's fortune in the stones.