Fragmentary dinosaur bone (possible Spinosaurid or Carcharodontosaurid fragment)
Spinosaurus aegyptiacus cf. or Carcharodontosaurus saharicus cf. • Body fossil; Vertebrate; Partial osteological element (permineralized)
Geological Period
Cretaceous (Cenomanian stage)
Estimated Age
95 - 100 million years
Preservation Type
Permineralization with heavy hematite/iron oxide replacement, resulting in the characteristic 'Kem Kem' red coloration.
Condition Assessment
Poor to Fair. The specimen is highly fragmentary, lacks diagnostic articular surfaces, and shows significant post-depositional weathering.
Taxonomic Classification
Phylum: Chordata; Class: Reptilia; Order: Saurischia; Suborder: Theropoda; Family: Indeterminate (likely Spinosauridae or Carcharodontosauridae)
Morphological Description
A fragmentary specimen showing a highly porous inner trabecular (cancellous) bone structure surrounded by a thin layer of denser cortical bone. The surface shows a rugged, pitted texture typical of weathered theropod bone with deep red-brown iron mineralization.
Rock Matrix
Reddish ferruginous sandstone/siltstone with traces of yellow goethite and dark manganese or hematite staining.
Formation & Location
Kem Kem Group (formerly Kem Kem Beds), Morocco, North Africa.
Size & Dimensions
Approximately 4-6 cm in width. Small for a dinosaurian element, representing a fragment of a much larger limb or vertebrae assembly.
Value & Rarity
Estimated Market Value
$15.00 - $35.00
Auction Estimate
$20.00 - $40.00 (usually sold in lots)
Rarity Assessment
Common. Chunk-of-bone (COB) fragments from the Kem Kem beds are some of the most widely available dinosaur fossils on the global market.
Scientific Significance
Provides evidence of the diverse megafauna in the Cretaceous fluvial systems of North Africa, though its lack of diagnostic features limits its utility for specific evolutionary studies.
Preparation Recommendations
No further mechanical preparation is recommended. Conservation involves stabilization with a reversible consolidant like Paraloid B-72 to prevent further crumbling of the iron-rich matrix.
Notable Features
Distinguished by the intense 'blood red' iron mineralization and the visible vesicular structure of the inner bone marrow cavity.