fossil

Spinosaurus aegyptiacus Fossil

Spinosaurus aegyptiacus (permineralized hydroxyapatite)

Hardness: 5 (fossilized bone); Color: Dark brown to tan; Luster: Dull to earthy; Composition: Silica or calcium carbonate replacement of original bone; Structure: Fossilized vertebrate skeletal remains.

Hardness: 5 (fossilized bone)
Color: Dark brown to tan
Luster: Dull to earthy

Identified July 19, 2026More fossil →

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Physical properties

Formation & geological history

Formed during the Cretaceous period (approx. 95-99 million years ago) in North Africa (Cretaceous Kem Kem Group). Original bone material was replaced by minerals through permineralization in fluvial or deltaic environments.

Uses & applications

Scientific research, museum exhibition, and high-end private collecting. Essential for understanding dinosaur evolution and paleontological history.

Geological facts

Spinosaurus was the largest of all known carnivorous dinosaurs, even larger than T. rex. It is notable for the massive 'sail' on its back formed by tall neural spines and is considered a semi-aquatic predator.

Field identification & locations

Identified by long, crocodilian-like snouts and elongated neural spines. Commonly found in the Kem Kem beds of Morocco. Collectors look for specific dental patterns and bone density consistent with theropods.

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Chert with Fossil Brachiopod

Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion

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Fossiliferous Limestone

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Fossilized Crinoid Stem in Limestone

Crinoidea (Class) in Calcium Carbonate (CaCO3) matrix

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