Two Polyhedral Agates
Garguelo Farm, São José de Marimbas, Cachoeira dos Índios, Paraiba, Brazil
Discovered in the mid-1970s in the locality of Paraiba, Brazil, debates have arisen as to the origin of the shape of these agates. "Polyhedral" meaning "many-sided", these stunning agates formed in geometric pattern shapes rather than the more common round or oval agate shape. The theories of formation of these agates are still an ongoing debate among geologists. The most agreed upon theory seems to be that the sharp geometric shapes are thought to have been formed in the voids between interlaced crystals of Barite, or possibly Calcite crystal formations. Larger specimens, such as these, are now rare in the marketplace as most have been cut into cross-section slices. Measuring 15.5 x 5 x 11.2 cm and 16.5 x 6 x 3 cm (2)
