Legend of the Thunderegg:
The Native Americans of Central Oregon gave the Thunderegg its name. It was believed that the Thunder Spirits that lived on Mount Jefferson and Mount Hood were jealous rivals. While in battle the Thunder Spirits threw large numbers of these eggs at each other during thunderstorms. It has also been said that Thundereggs are the eggs laid by the Thunderbird.
During the Eocene Age,60 million years ago, it is believed that rhyolite lava flows covered large portions of Oregon. Bubbles of volcanic gas formed in the lava flow and became solid as the lava cooled. Over time the bubbles cracked allowing silica dense water to fill the empty space. It is silica (quartz) and other minerals that create the amazing patterns inside of the rhyolite shell. No two rocks are identical.
The Thunderegg became the state rock of Oregon in 1965.
This specimen weighs 13.6-ounces and comes from Richardson’s Rock Ranch in Madras, Oregon. It was cut and polished in our lapidary workshop.