Coprolite (Fossilized Dung)
Indeterminate reptile or mammal species; often referred to as cf. Crocodylus or similar large prehistoric reptile based on morphology • Trace fossil (Ichnofossil) - fossilized excrement
Geological Period
Miocene to Pleistocene (likely Neogene period)
Estimated Age
Approximately 2.5 to 20 million years
Preservation Type
Permineralization and replacement; mineralized primarily with iron oxides and phosphate materials (phosphatic preservation)
Condition Assessment
Good condition; largely intact with well-defined surface texture, although displaying common natural fractures and some weathering.
Taxonomic Classification
Kingdom: Animalia; Ichnogenus: Likely attributed to ancient reptiles or crocodilians (Indeterminate Sauropsida)
Morphological Description
Irregular, lumpy, and bulbous morphology with distinct convolutions and segments. The surface exhibits a rough, rugose texture with cracks and desiccated appearance consistent with fecal matter that hardened prior to fossilization. No visible inclusions like bone fragments or scales on the exterior surface.
Rock Matrix
Minimal remaining matrix; appears to be a cleaned specimen. Associated matrix would typically be fine-grained siltstone or mudstone.
Formation & Location
Likely from the Wilkes Formation (Washington State, USA) or similar lacustrine/riverine deposits in the Southeastern United States or Madagascar.
Size & Dimensions
Approximately 5cm to 8cm in diameter; within the standard size range for medium-to-large vertebrate coprolites.
Value & Rarity
Estimated Market Value
$15.00 - $35.00 USD
Auction Estimate
$20.00 - $50.00 USD
Rarity Assessment
Common; coprolites are widely found in specific fossiliferous strata, though well-formed specimens are locally uncommon.
Scientific Significance
Provides vital paleoecological data regarding the diet of prehistoric fauna, digestive processes, and the presence of specific animal groups in ancient freshwater or terrestrial ecosystems.
Preparation Recommendations
Stable as is; requires no chemical treatment. Should be kept in a low-humidity environment. Display with a stand to highlight texture without handling.
Notable Features
Features classic 'pinch marks' and deep desiccation cracks that occurred before petrification, confirming its identity as a trace fossil rather than a simple mineral concretion.