A series of volcanic eruptions buried the Cerro Cuadrado forest approximately 160 million years ago at a time when the Araucaria mirabilis conifer’s cones were reaching maturity.

Araucaria mirabilis is an extinct species of conifer from the Middle Jurassic, Cerro Cuadrado Petrified Forest, Patagonia, Argentina

Specimens are often cut and polished to reveal the true beauty of the internal structure of the cone in minute detail.

These cones were acquired at the Tucson, Mineral, Gem and Fossil show in the 1990’s from Ulrich Dernbach. After 2003 the Argentine government prevented any further export of the cones. As a result, these cones are now very sought after and will only become more rare.

These beautiful cones have become silicified by the process of mineralization. The water that percolated through the volcanic ash was absorbed into the cones who take on the color associated with the minerals that were prevalent in the ash.