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Kentucky's Official State Rock: Agate

Agate the State Rock

Agate became Kentucky's Official State Rock in the year 2000. This might be confusing, because scientifically agate is considered a variety of the mineral quartz. Minerals are the building blocks of rocks. Although rocks are generally thought of as sedimentary, metamorphic, and igneous types, collectors and hobbyists call varieties of some minerals rocks as well. Quartz has many varieties. Naturally occurring chemical impurities in the quartz can cause it to be colored. When different impurities occur in bands within quartz, the quartz will have a colorful, banded appearance, and it is then called agate.

Photographs of Kentucky Agate courtesy of Roland MacIntosh (copyrighted 1999).

Beautiful specimens of red, black, yellow, and gray banded agate have been discovered in Estill, Jackson, Powell, Madison, and Rockcastle Counties. These Kentucky agates are derived from the Renfro-Borden Formation of Early Mississippian age and can be collected along some river drainages where the Borden is exposed to weathering.

Kentucky House Amendment that made agate the State Rock

Kentucky Agate for pictures of Kentucky agates

Rocks and Minerals of Kentucky for summary of rocks and minerals in the state

Rocks and Minerals Key Links for information about rocks and minerals around the world


Official text of the Bill that designated agate as the Official State Rock

The following text was copied from the Kentucky Legislature, Legislative Record on line at (April, 2001)

House Bill 123

(BR 318) - J. Bowling, J. Adams, R. Adkins, S. Alexander, J. Arnold Jr., A. Arnold, B. Ausmus, III, E. Ballard, S. Baugh, C. Belcher, L. Belcher, I. Branham, K. Bratcher, B. Buckingham, T. Burch, De. Butler, Dw. Butler, J. Callahan, P. Childers, L. Clark, B. Colter, J. Crenshaw, R. Damron, B. DeWeese, J. Draud, J. Fischer, J. Gooch, G. Graham, J. Gray, B. Heleringer, C. Hoffman, J. Hoover, D. Horlander, S. Johns, E. Jordan, M. Marzian, T. McKee, C. Miller, L. Napier, F. Nesler, R. Palmer, R. Palumbo, M. Rader, T. Riner, A. Simpson, J. Stacy, K. Stein, G. Tapp, R. Thomas, M. Treesh, J. Turner, K. Upchurch, C. Walton, J. Wayne, M. Weaver, R. Wilkey, P. Worthington, B. Yonts

AN ACT relating to the designation of the official rock of Kentucky.

WHEREAS, the colorful rock, Kentucky agate, bears the name of this great Commonwealth; and

WHEREAS, this beautiful Kentucky resource, 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; and

WHEREAS, designation of a state rock will promote interest in geology, the hobby of mineral collecting, and the lapidary arts;


Be it enacted by the General Assembly of the Commonwealth of Kentucky:


Kentucky agate is named and designated as the official rock of Kentucky.

Signed by the Governor on March 23, 2000


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