Fossiliferous conglomerate with indeterminate faunal remains
Indeterminate cf. Rhynchonellida or Crinoidal columnals • Body fossil / Shelly hash; Invertebrate classification
Geological Period
Likely Carboniferous to Permian
Estimated Age
250 to 350 million years
Preservation Type
Recrystallization and replacement (likely calcitic or siliceous replacement)
Condition Assessment
Poor/Fair; heavily weathered and fragmented, with no complete biological structures preserved
Taxonomic Classification
Phylum: Echinodermata (likely Crinoidea fragments) and/or Brachiopoda
Morphological Description
Small, fragmented rounded and angular clasts embedded in a dense matrix. Visible features include potential stem segments (columnals) and fractured shell outlines with faint ribbing patterns.
Rock Matrix
Ferruginous sandstone or siltstone (Red Bed) matrix, characterized by iron oxide staining
Formation & Location
Likely sourced from a formation such as the Cutler or Hermosa Groups (North America) or similar continental 'Red Bed' deposits containing marine influx layers
Size & Dimensions
Approximately 5-8 centimeters across (clast sizes range from 2mm to 10mm)
Value & Rarity
Estimated Market Value
$5.00 - $15.00 USD
Auction Estimate
$10.00 - $30.00 USD (as a bulk study lot)
Rarity Assessment
Common; such fossil hashes and conglomerates are ubiquitous in marine-terrestrial transition zones
Scientific Significance
Low; provides evidence of high-energy depositional environments and marine transgression into terrestrial basins, but lacks diagnostic individual specimens
Preparation Recommendations
No invasive preparation suggested. Clean with a soft brush and dry cloth. Store in a low-humidity environment to prevent further oxidation of the iron-rich matrix.
Notable Features
Distinctive reddish-brown coloration due to hematite or goethite staining within the matrix, typical of ancient river delta or shallow marine shelf transitions.