Fossil Seed Fern (Neuropteris / Alethopteris)
cf. Neuropteris sp. or Alethopteris sp. (Piesberg Coal Measures type) • Compression/Impression body fossil of plant foliage (Paleobotanical)
Geological Period
Late Carboniferous (Pennsylvanian / Westphalian)
Estimated Age
305 to 315 million years old
Preservation Type
Carbonaceous compression and impression with partial iron-oxide mineral alteration/staining along the plant structure.
Condition Assessment
Good. Multiple pinnules are well-preserved with clear vein details, though the specimen consists of fragmented frond sections across uneven matrix planes.
Taxonomic Classification
Kingdom: Plantae, Phylum: Tracheophyta, Class: Pteridospermatopsida (Seed Ferns), Order: Medullosales, Family: Neuropteridaceae / Alethopteridaceae
Morphological Description
Multiple overlapping pinnae with well-defined, tongue-shaped pinnules attached to a central rachis. Distinct venation pattern is visible, branching outward from a central midvein toward the leaf margins. Slightly golden-brown oxidation contrasts against the dark matrix.
Rock Matrix
Dark grey to black bituminous shale / siltstone matrix, characteristic of coal-bearing strata (Coal Measures).
Formation & Location
Piesberg Quarry near Osnabrück, Lower Saxony, Germany (Piesberg Formation, Pennsylvanian).
Size & Dimensions
Hand specimen measuring approximately 6 to 8 cm across, with individual pinnules ranging from 5 mm to 15 mm in length.
Value & Rarity
Estimated Market Value
$15 - $35 USD
Auction Estimate
$20 - $40 USD
Rarity Assessment
Common to locally abundant at classic sites like Piesberg, but desirable due to clear local provenance and fine venation preservation.
Scientific Significance
Represents classic Westphalian flora from coastal swamp forests of Laurussia. Provides insights into Late Paleozoic tropical coal-swamp ecosystems and early seed-bearing plant evolution.
Preparation Recommendations
No heavy mechanical preparation required. Keep in a stable, low-humidity environment to prevent shale degradation or pyrite oxidation. Display flat or mounted on an easel.
Notable Features
Clear venation details on pinnules and distinctive iron-oxide contrast against dark slate-like matrix. Direct locality association with the famous Piesberg quarry near Osnabrück.
Notes
Osnabruk