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Thundereggs: Oregon's State Rock
6m 40s
/ TV-G
Oregon's high desert from Madras to the Ochoco Mountains has some of he largest deposits of thundereggs in the world. Rock hounds slice them open to find agate, jasper, opal, sometimes in ornate patterns, hidden inside, the first people in history to ever see the formations since they were encased in cooling lava 60 million years ago. Thundereggs were named the state rock of Oregon in 1965.