sedimentary (fossiliferous)

Fossil Shark Tooth (Otodus obliquus)

Otodus obliquus; hydroxyapatite (mineralized form Ca5(PO4)3(OH))

Hardness: 5 on Mohs scale; Color: Tan to light cream/yellow brownish; Luster: Vitreous to dull; Structure: Triangular crown with lateral cusplets and a thick root; Specific gravity: Approx 3.1

Hardness: 5 on Mohs scale
Color: Tan to light cream/yellow brownish
Luster: Vitreous to dull

Identified March 9, 2026More sedimentary (fossiliferous) →

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Physical properties

Hardness: 5 on Mohs scale; Color: Tan to light cream/yellow brownish; Luster: Vitreous to dull; Structure: Triangular crown with lateral cusplets and a thick root; Specific gravity: Approx 3.1

Formation & geological history

Formed through permineralization where silica and phosphate replaced original organic structure. Occurs in marine sedimentary layers, primarily from the Paleocene to Eocene epochs (approx. 40-60 million years ago).

Uses & applications

Predominantly used for biological research, educational displays, jewelry (pendants), and as a popular entry-level item for fossil collectors.

Geological facts

Otodus obliquus was a prehistoric mackerel shark and a direct ancestor to the famous Megalodon. Most fossils of this species are found in Morocco, specifically in the Khouribga phosphate mines.

Field identification & locations

Identify in the field by searching for triangular silhouettes in phosphate-rich sediment or riverbeds; look for the distinct 'root' which is often sand-textured compared to the smooth enamel crown. Common in North Africa and the Eastern USA.

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