Geode Interior
(c) 2002 Andrew Alden, licensed to About.com, Inc. (fair use policy)
Here's the kind of thing I bought those geodes to find. My brother-in-law found this example in the Utah desert near Tooele, had it sawed open, and turned it into a pair of bookends. The crust is a finely layered siliceous material. The inner cavity is lined with crusts of clear silica, laid down in different layers as climate changes altered the state of the groundwater. The crown of the geode, on the right side, is lined with clear quartz crystals.
Not having a diamond saw on the premises, I instead took out my trusty rock hammer and broke my geodes. I had high hopes, because they felt light in my hand. Next . . . >
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