Glossopteris Leaf Impression
Glossopteris cf. indica • Plant body fossil; carbonaceous impression/compression
Geological Period
Permian
Estimated Age
252 to 299 million years
Preservation Type
Carbonization/Impression: The organic material has been largely replaced or compressed into a thin carbon film, leaving a detailed dark imprint on the lighter substrate.
Condition Assessment
Fair: The midrib is well-defined, but the leaf margins are incomplete and the distal/proximal ends are missing; the matrix is stable but roughly weathered.
Taxonomic Classification
Kingdom: Plantae, Division: Pteridospermatophyta, Order: Glossopteridales, Family: Glossopteridaceae, Genus: Glossopteris
Morphological Description
The specimen shows a partial leaf blade with a distinct, thick midrib (central vein) and a faint reticulate (net-like) venation pattern emerging from it. The leaf margin appears entire, though the specimen is fragmented.
Rock Matrix
Ferruginous (iron-rich) siltstone or fine-grained sandstone with a characteristic reddish-orange ochre hue due to hematite/limonite staining.
Formation & Location
Likely the Illawarra Coal Measures or Dunedoo region of New South Wales, Australia; also common in the Karoo Basin, South Africa and the Damodar Valley, India.
Size & Dimensions
Approximately 5-7 cm in length; representing a partial section of a leaf that can typically reach 10-30 cm in length depending on the species.
Value & Rarity
Estimated Market Value
$15 - $35 USD
Auction Estimate
$20 - $50 USD
Rarity Assessment
Common: Glossopteris is the most abundant plant fossil of the Southern Hemisphere Permian deposits.
Scientific Significance
Crucial evidence for the theory of Continental Drift (Gondwana). The widespread distribution of this genus across South America, Africa, Antarctica, India, and Australia provided Alfred Wegener with key evidence for Pangea.
Preparation Recommendations
No invasive preparation needed; clean with a soft dry brush. Keep in a low-humidity environment to prevent further oxidation of the iron-rich matrix.
Notable Features
The specimen exhibits a sharp contrast between the dark carbonized veins and the oxidized red matrix, making the venation visible without magnification.