Petrified Wood (Polished Specimen)
Indeterminate woody plant taxon (cf. Araucarioxylon sp. or similar permineralized wood species) • Body fossil (permineralized plant tissue), Plant / Paleobotanical classification
Geological Period
Triassic to Paleogene (commonly Late Triassic Chinle Formation or Eocene Green River Formation context)
Estimated Age
50 to 225 million years old
Preservation Type
Permineralization / Silicification (agate, chalcedony, and quartz replacement of organic wood cellular structures)
Condition Assessment
Fair to Good. Specimen is cut and polished showing interior mineral replacement, but exhibits natural fracture planes and minor edge wear.
Taxonomic Classification
Kingdom: Plantae, Division: Tracheophyta, Class: Pinopsida / Magnoliopsida (Indeterminate gymnosperm or angiosperm trunk section)
Morphological Description
Blocky, cut, and polished rectangular section displaying varied coloration including earthy brown, ochre, white, and translucent bluish-gray agate replacement pockets. Preserved cellular replacement and growth structure lines are visible internally despite fracturing.
Rock Matrix
Silicified wood matrix with microcrystalline quartz and jasper/agate infilling, set without host matrix.
Formation & Location
Commonly sourced from Chinle Formation (Arizona/Utah, USA), Madagascar, or Indonesia (West Java).
Size & Dimensions
Approximately 5 cm to 8 cm in height, representative of a small hand specimen or polished block offcut.
Value & Rarity
Estimated Market Value
$10 - $25 USD
Auction Estimate
$15 - $35 USD
Rarity Assessment
Common; permineralized wood with agate/jasper mineralization is abundant worldwide.
Scientific Significance
Illustrates the process of permineralization where organic cellular structures are replaced molecule-by-molecule by silica-rich groundwater, providing insights into ancient forest composition and paleoclimatology.
Preparation Recommendations
Keep dry and clean using a soft microfiber cloth; display away from extreme physical impact to prevent splitting along natural fracture planes.
Notable Features
Features distinct color zoning ranging from dark iron-rich browns and yellow ochres to a distinct translucent grayish-blue chalcedony pocket in the center.