Ediacaran biota (Descriptive: Discoidal or multi-lobed impression)
cf. Aspidella terranovica or Dickinsonia sp. • Trace fossil/Impression of soft-bodied organism (Invertebrate/Metazoan precursor)
Geological Period
Ediacaran Period (late Neoproterozoic)
Estimated Age
550 - 635 million years
Preservation Type
Cast and mold impression (Ediacaran-style preservation) often mediated by microbial mat 'death masks'.
Condition Assessment
Fair to Good; the relief is relatively low and weathered, making diagnostic features difficult to discern without low-angle lighting.
Taxonomic Classification
Kingdom: Animalia (incertae sedis); Phylum: Petalonamae (potential affinity); Family: Dickinsoniidae or Aspidellidae (cf.)
Morphological Description
Specimen exhibits faint, circular to sub-ovate impressions with potential evidence of central depressions and radial ornamentation. The surface shows a slightly raised, textured topography indicative of a soft-bodied organism compressed against a microbial mat.
Rock Matrix
Ferruginous (iron-rich) siltstone or fine-grained sandstone, showing characteristic 'Red Bed' coloration from hematite/limonite staining.
Formation & Location
Likely Mistaken Point (Newfoundland, Canada), White Sea (Russia), or the Flinders Ranges (Australia), specifically within the Rawnsley Quartzite or similar siltstone formations.
Size & Dimensions
Approximately 5-8 cm in diameter; consistent with average sizes for early discoidal Ediacaran biota.
Value & Rarity
Estimated Market Value
$150 - $450 USD
Auction Estimate
$200 - $600 USD
Rarity Assessment
Uncommon; while specific sites are rich, authentic Ediacaran specimens are geographically limited and highly regulated in many regions.
Scientific Significance
Crucial for understanding the 'Cambrian Explosion' precursor; provides evidence of the earliest complex multicellular life forms and the evolution of body symmetry.
Preparation Recommendations
No chemical cleaning; avoid abrasive mechanical prep. Stabilize with a dilute archival consolidant (Paraloid B-72) if flaking occurs. Display with side-lighting to enhance relief.
Notable Features
The specimen features a distinct reddish-brown mineralization which suggests an aerobic depositional environment or post-depositional oxidation, typical of certain South Australian or Canadian outcrops.