Name/Title
Polished Petrified Conifer Stump (Araucarioxylon arizonicum)Description
Polished Petrified Conifer Stump
Araucarioxylon arizonicum
Late Triassic
Chinle Formation
Arizona, United States
This specimen is a polished section of petrified conifer wood identified as Araucarioxylon arizonicum, a tree related to the ancient lineage of araucarian conifers. These trees formed extensive forests across what is now the American Southwest during the Late Triassic Period, more than 200 million years ago, at a time when dinosaurs were only beginning to diversify.
Petrified wood forms through a slow process of mineral replacement. After burial by sediment, silica-rich groundwater permeated the fallen tree, gradually replacing organic material cell by cell with minerals—most commonly quartz—while preserving the microscopic structure of the wood. The polished surface of this stump reveals the internal anatomy of the tree in striking detail: growth rings, vascular patterns, and subtle color variations produced by trace minerals introduced during fossilization.
The Chinle Formation is one of North America’s most important Triassic fossil deposits, documenting river systems, floodplains, and forests that existed in a warm, seasonally wet climate. Petrified wood such as this provides direct evidence of these ancient ecosystems and helps reconstruct both the vegetation and environmental conditions of the period.
As both a geological and biological record, this specimen bridges deep time, transforming a once-living tree into stone while retaining the structural memory of its growth.
Dimensions: 5.98 × 4.07 × 3.43 inches (15.20 × 10.33 × 8.71 cm)Create Date
December 19, 2025Update Date
January 12, 2026
