Petrified Wood / Fossilized Conifer Bark
cf. Araucarioxylon arizonicum • Body fossil (permineralized plant tissue), Plant/Paleobotanical
Geological Period
Triassic (Late Triassic)
Estimated Age
201 to 230 million years
Preservation Type
Permineralization (Silicification with iron oxide staining)
Condition Assessment
Fair to Good; highly fragmented and weathered with some loss of fine anatomical detail, but retains diagnostic grain structure.
Taxonomic Classification
Kingdom: Plantae, Division: Pinophyta, Order: Pinales/Araucariales, Genus: cf. Araucarioxylon
Morphological Description
The specimen exhibits clear longitudinal striations and fibrous textures characteristic of secondary xylem (wood). One side shows a rough, rugose texture consistent with external bark or cambium layers, while the fractured surfaces reveal dense, silicified cellular structures. There is evidence of tracheid-like alignment under magnification.
Rock Matrix
Ferruginous sandstone/siltstone matrix characteristic of the Chinle Formation.
Formation & Location
Chinle Formation, Painted Desert or Petrified Forest National Park region, Arizona, USA.
Size & Dimensions
Approximately 5-8 cm in length; a small hand-sample/fragment typical of float material found in desert washes.
Value & Rarity
Estimated Market Value
$10.00 - $25.00 USD
Auction Estimate
$15.00 - $30.00 USD
Rarity Assessment
Common; while the Chinle wood is world-famous, small unpolished fragments are extremely abundant.
Scientific Significance
Provides evidence of the lush, river-basin ecosystems and massive conifer forests that dominated Pangaea during the Late Triassic, helping track paleoclimate shifts from humid to arid environments.
Preparation Recommendations
Best displayed cross-cut and polished to reveal internal cell structure; store in a dry environment to prevent any potential oxidation of trace minerals.
Notable Features
Distinctive deep red/terracotta coloration indicating high iron oxide content during the petrification process; features a transition between dense interior wood and weathered outer surface.