Iowa State Rock – The Geode

The History of the Iowa State Rock

The Iowa General Assembly designated the geode as the official state rock in 1967.

Many geodes are solid, like this one, when they are broken open. The colors are caused by various minerals, and can range anywhere along the colors of the rainbow. Geode - Photo by Andre Carol

Because Iowa is well known for the presence of the Geode, it was chosen as the official rock in an effort to promote tourism in the state. Legislators who favored making the Geode the state rock pointed out that it is among the rarest and most beautiful of rocks and that Iowa is known worldwide because of the large number found in the state. Other rocks considered for official status were limestone and fossil coral.

In Latin, the word “geodes” means “earthlike.” Geodes are shaped like the earth and average about four inches in diameter. Geodes are found in limestone formations and have a hard outer shell. When carefully broken open, a sparkling lining of mineral crystals, most often quartz and calcite, is revealed.

Southeastern Iowa is one of the state’s best Geode collecting areas. Geode State Park, in Henry County, is named for the occurrence of the Geode.

Source: Iowa State Legislature

 

 

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Learning Links for Geodes – The Iowa State Rock

Iowa State Rock
Learn all about geodes, their origins, and much much more.
Source:Iowa Department of Natural

Iowa State Rock (Pamplet) (Adobe Acrobat Required)
Print this foldable pamphlet with fantastic information on the Iowa state rock, the geode.
Source:Iowa Department of Natural Resources

Iowa State Rock (Geode)
Learn all about geodes, how they’re created, and where they can be found.
Source: Columbus Junction, Iowa