Agates from MexicoThis Laguna agate half showcases the classic fortification banding that makes this locality famous. The alternating pink, white, and lavender bands formed as silica-rich solutions deposited successive layers in a volcanic cavity. The irregular, angular banding pattern creates optical depth through refractive index variations between the chalcedony layers. Notice how the band thickness varies - this indicates fluctuating silica concentration during formation. 🔬
