Has everyone else been loving Mike Stoklasa (aka Mr. Plinkett's) savage reviews of the prequels? I sure have, but he also did some other really cool stuff like this fun rock and geology themed musical. The main character is a Geologist.
Overall good fun, but a few geology nitpicks...gypsum is mentioned as a hard mineral, but actually it's a 2 on the Mohr hardness scale - your fingernails are about 2.5! Diamonds are a 10. A good mnemonic device for remembering Mohr's scale is "The Green Clawed Ferocious Aardvark Ordered Quick Tasty Chinese Dinners."
Also, Quartzite actually isn't related to good old SiO2 at all, but is just a metamorphic sandstone.
Cobalt is an element and lucite is clear white stuff used instead of glass that's not found in the earth at all.