Fossilized Shark Tooth
Cosmopolitodus hastalis (Broad-toothed Mako/Extinct Giant Mako) or cf. Carcharodon carcharias • Body fossil; Vertebrate (Chondrichthyes)
Geological Period
Neogene (likely Miocene or Pliocene)
Estimated Age
5 million to 23 million years
Preservation Type
Permineralization; characteristic dark 'beach-worn' appearance indicating secondary transport.
Condition Assessment
Fair; the tip is intact and edges are relatively sharp, but the root is mostly eroded and the specimen shows signs of water-worn tumbling.
Taxonomic Classification
Phylum: Chordata, Class: Chondrichthyes, Order: Lamniformes, Family: Lamnidae, Genus: Cosmopolitodus (or Carcharodon)
Morphological Description
A triangular, unserrated crown with smooth cutting edges. The crown is dark, likely due to phosphate mineralization. The root area is partially missing or heavily worn, but shows a characteristic shape for Lamniformes. The blade is flat on the labial side and slightly convex on the lingual side.
Rock Matrix
None (isolated find). Likely originated from phosphate-rich marine sediments before being weathered into a beach deposit or river gravel.
Formation & Location
Commonly found in the Peace River Formation (Florida), Yorktown Formation (East Coast USA), or similar coastal Neogene deposits globally.
Size & Dimensions
Approximately 1 inch (2.5 cm) in length; small for this genus which can reach sizes over 3 inches.
Value & Rarity
Estimated Market Value
$5 - $15 USD
Auction Estimate
$10 - $20 USD (usually sold as part of a larger lot)
Rarity Assessment
Common; isolated teeth of this species are found in high concentrations in specific geological lag deposits.
Scientific Significance
Provides data on Miocene marine biodiversity and the presence of apex predatory sharks in ancient shelf environments; useful for biostratigraphy.
Preparation Recommendations
Minimal; gentle cleaning with water and a soft brush. Scale/paraloid coating is not necessary for this level of mineralization. Display in a protective acrylic case.
Notable Features
The smooth edges distinguish it from Great White or Megalodon teeth. The dark coloration is typical of specimens found in the southeastern United States.