Description

#3207 – 2.5 x 1.6 x 1.4 -inch polished Agate nodule featuring red to pink fortification bands of cryptocrystalline Quartz from the Dry Head region of Montana.  Dryhead agates originated in sedimentary rocks of the Bighorn Canyon area in Montana, forming as concretions within clay-shale and siltstone. They developed from silica-rich fluids filling cavities, likely around organic material, and are known for their beautiful, hidden banding. The area is geologically part of the Phosphoria Formation, and the agates are now very rare because the mining area is largely closed off.