MINERAL OF THE MONTH
February 2010 – Kentucky Agate
Several states have designated agate as either their state stone or their state mineral. In the next few web page updates, I’ll feature these officially recognized agates. This month, it is the Kentucky agate. This past summer, Mary Collings, donated some unpolished slabs of Kentucky agate to the museum. A picture of one of the slabs is on the home page. Others are included below. All of these photos were taken by Tom Shearer for the new agate book. He told me that of the thousands of photos he has taken, from which we had to select the ones to use in the book, that the Kentucky agates were one of the biggest surprises. To see more of Tom’s photos, please go to his Flickr page at: http://www.flickr.com/photos/tshearer/.
In 2000, the Kentucky Agate became the official state rock. The language in the legislative bill stated that the agate is “characterized by delicate bands of blue, red, orange, black, yellow, or gray shades, is often displayed at local rock shows and used as an ornamental material and in semiprecious jewelry.” The bill also said that “designation of a state rock will promote interest in geology, the hobby of mineral collecting, and the lapidary arts.” This designation was somewhat of a surprise since the agate has always had a secretive stigma, most likely because they are usually found on private land.
This distinctive agate was formed in shale and siltstone in the Borden layer of the Mississippian geologic period between 225 and 375 million years ago. These agates can be found in Estill, Jackson, Lee and Powell Counties, especially in the Buck, White Oak, and Middle Fork Creeks.
Mineral of the Month Archives
May 2007 Rainbow Fluorite
June 2007 Lake Superior Michipicoten Agate
July 2007 Labadorite
August 2007 Rain Flower Agate
Fall 2007 Malachite
December 2007 Nepheline Syenite
January 2008 Native Copper
February 2008 Amazonite
March 2008 Lake Superior Agate
April 2008 Shadow Agate
May 2008 Apohpylite
June 2008 Ocean Jasper
Summer 2008 Marra Mamba Tiger's Eye
September 2008 Mohawkite
October 2008 Mexican opal
November 2008 Prehnite
December 2008 Picture Jasper
January 2009 Sea Shell Jasper
February 2009 Polychrome Jasper
March 2009 Selenite Desert Rose
Spring 2009 Coyamito Agate
July 2009 Obsidian Needles
August 2009 Goethite
September 2009 Banded Iron Formation
Fall 2009 Fairburn Agate
February 2010 Kentucky Agate
March 2010 Fossilized Dinosaur Bone
April/May 2010 Kentucky Agate
June 2010 Nantan Meteorite
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Gitche Gumee Museum.
E21739 Brazel Street
Grand Marais, Michigan 49839





