Agatized Petrified Wood / Silicified Wood Fragment
Indeterminate genus and species (requires thin-section microscopic analysis of cellular structure) • Body fossil (permineralized plant material); Invertebrate Paleobotany
Geological Period
Likely Cretaceous to Neogene (potentially Jurrasic)
Estimated Age
Approximately 15 to 150 million years
Preservation Type
Permineralization (Silicification); cellular structure replaced by cryptocrystalline quartz (chalcedony/agate)
Condition Assessment
Fair to Good; it is a water-worn fragment with rounded edges, lack of bark, and significant weathering/abrasion.
Taxonomic Classification
Kingdom: Plantae; Phylum: Tracheophyta; Class: Pinopsida (conifer-like) or Magnoliopsida (hardwood)
Morphological Description
Elongated fragment showing distinct parallel longitudinal grain patterns and growth rings. Texture is glassy to waxy due to silica replacement, with visible tracheid fiber orientation.
Rock Matrix
Specimen is self-contained (water-worn pebble); likely eroded from a sedimentary mudstone or sandstone fluvial deposit.
Formation & Location
Common in formations like the Morrison (USA), Hell Creek (USA), or various Cenozoic gravel deposits globally.
Size & Dimensions
Approximately 4-6 cm in length; typical for small water-tumbled stream or beach cobbles.
Value & Rarity
Estimated Market Value
$5.00 - $15.00 USD
Auction Estimate
$10.00 - $25.00 USD (as part of a bulk lot)
Rarity Assessment
Common; petrified wood is globally abundant in many geological settings.
Scientific Significance
Provides evidence of ancient forest composition and paleoclimatic conditions; silicified wood indicates high-silica volcanic ash or groundwater environments.
Preparation Recommendations
Polishing one or more faces would better reveal the internal grain structure and coloration. Store in a dry environment.
Notable Features
Distinct 'feathering' pattern of the wood grain and amber-to-brown iron staining within the translucent agate matrix.