#craspedites

[transparentfossil]

Craspedites nodiger

[confusedhadrosaur]

Ophthalmothule cryostea & Craspedites okensis from the Jurassic-Cretaceous boundary (Tithonian/Berriasian,  ~145 Ma), Norway

[pearl-nautilus]

This spectacular ammonite, known as Craspedites nodiger, has chambers preserved as grayish-white Calcite crystals, with the septa (divisions) between each chamber preserved as black Calcite. The intricate suturing that provided strength for the shell at low weight expense, an important feature for an animal, which relied on near neutral buoyancy to allow it to move freely throughout the water column, is readily seen here. It is this delicate suturing for which these ammonites are well known. This is a large example of an ammonite from the Tithonian Stage (150 m.y.a) deposits of Russia.

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