Teepee canyon agates are from the Black Hills of South Dakota (Teepee Canyon is also known as Hell’s Canyon). They have beautiful intricate tight bands of reds and oranges and often have druzy pockets. Collection from teepee canyon is no longer permitted, making these agates rare and increasingly hard to find through sellers.
Agates form within chert nodules in the Minnelusa Limestone. Most of the nodules are plain gray or have red jasper. The fortification agates are hard to find within this hard limestone. The trademark holly-leaf pattern in the fortification is even more rare and precious. Fairburn agates that are found in the gravels on the plains east of the Black Hills are now known to have originated in the bedrock at Teepee Canyon and other places in the Black Hills where the Minnelusa Formation is exposed. Throughout most of the Black Hills, the nodules in the Minnelusa Formation do not show the fortification and colors seen at Teepee Canyon.
Holly leaf fortification with quartz druzy center (specimen 6029)
Intricate fortification patterns of teepee canyon agate