Display pieces from the phosphate mines
A mosasaur jaw with a row of teeth in place is one of the most striking fossils to come out of Morocco. These pieces are found in the upper Maastrichtian phosphate beds of the Oulad Abdoun Basin around Khouribga, the same layers that produce isolated mosasaur teeth. Skulls and jaws can come from animals between about 2 m and over 10 m long, so sizes range from a hand-held jaw section to a skull more than a meter long[4].
They are also the category where honest description matters most. Fossil bones in the phosphates are often scattered and broken by mining, so complete jaws and skulls are rare finds.
How a Moroccan mosasaur jaw is made ready for sale
Most mosasaur jaws and skulls on the market have been worked on, sometimes a little, sometimes heavily. Common steps include:
- Repair: broken bone glued back together and cracks filled.
- Restoration: missing bone sculpted in filler and painted to match.
- Tooth setting: loose teeth from the same beds glued into empty sockets, or into a plaster or resin bed.
- Composites: jaw sections or skull bones from more than one individual combined into one piece.
This is normal in the trade and even in museum mounts. A Moroccan elasmosaur skeleton now on display in the USA, for example, has a skull largely reconstructed in three dimensions, many cast vertebrae, and jaw teeth replaced with isolated teeth from the same formation[3]. The problem is not restoration itself; it is restoration that is not declared.
The issue reaches scientific specimens too. In 2024 a team argued that teeth in the type jaw of the Moroccan mosasaur Xenodens had been set artificially[1]. The original authors answered in 2025 with CT scans that, they report, show continuous crown-root junctions and original phosphate matrix in the pulp cavities, with no glue or plaster visible[2]. The debate shows both how common tooth setting is and how it can be tested.
| Scientific name | Mosasauridae (Mosasaurus, Prognathodon, Halisaurus, others) |
|---|---|
| Geological age | Late Maastrichtian, Late Cretaceous (about 68–66 million years) |
| Formation | Phosphate series, upper Couche III |
| Locality in Morocco | Oulad Abdoun Basin, Khouribga Province |
| Typical size | Jaw sections about 15–60 cm; skulls up to about 1.4 m |
How to evaluate a mosasaur jaw or skull before buying
- Ask for a restoration statement. Which parts are original bone, which are filler, and were the teeth found in this jaw?
- Use UV light. Under long-wave UV, glues, resins and many fillers fluoresce differently from fossil bone and enamel, revealing repaired zones.
- Check the matrix. Original phosphate matrix is gritty and varied. A smooth, even paste, especially around tooth bases, suggests a plaster bed.
- Look at the tooth bases. Natural teeth sit in sockets in the bone with a continuous junction. Gaps, glue lines or teeth that stop at the surface are signs of setting.
- Check the tooth count and spacing. Mosasaurs have one functional tooth per socket. Crowded crowns, or teeth that differ sharply in size and color along one row, need explaining[1].
- For high-value pieces, ask about CT scanning. It is the most reliable way to see inside a specimen[2].
Choosing a piece for a store or gallery
Match the piece to its setting. A mosasaur jaw section of 15–30 cm suits a counter case and sells faster; long jaws and skulls need a dedicated stand and wall or floor space. Ask for the weight with base, since phosphate matrix blocks are heavy and affect freight cost. Large pieces travel in custom crates with export paperwork; see shipping.
How we list skulls and jaws
Every mosasaur jaw and skull on FossilSupplier.com carries a statement of whether it is natural, repaired or restored, together with locality, geological age, size and weight. We name a genus only where the bone and teeth support it. Request extra photos, including UV shots, before you buy.
Museum stores and galleries can request a quote for single display pieces, and trade buyers can apply for a wholesale account. Browse all mosasaur fossils or the wider range of marine reptile fossils.
References
- Sharpe, H. S., Powers, M. J. & Caldwell, M. W. (2024). Reassessment of Xenodens calminechari with a discussion of tooth morphology in mosasaurs. The Anatomical Record. doi:10.1002/ar.25612
- Longrich, N. R., Bardet, N., Jalil, N.-E., Pereda-Suberbiola, X., Schulp, A. & Ghamizi, M. (2025). New information on the morphology and tooth replacement of Xenodens calminechari (Squamata: Mosasauridae), a unique mosasaurid from the Maastrichtian Phosphates of Morocco. Diversity 17(12): 819. doi:10.3390/d17120819
- Lomax, D. R. & Wahl, W. R. (2013). A new specimen of the elasmosaurid plesiosaur Zarafasaura oceanis from the Upper Cretaceous (Maastrichtian) of Morocco. Paludicola 9(2): 97–109. PDF
- Bardet, N., Fischer, V., Jalil, N.-E., Khaldoune, F., Khadiri Yazami, O., Pereda-Suberbiola, X. & Longrich, N. (2025). Mosasaurids bare the teeth: an extraordinary ecological disparity in the Phosphates of Morocco just prior to the K/Pg crisis. Diversity 17(2): 114. doi:10.3390/d17020114
Frequently asked questions
Are Moroccan mosasaur jaws real?
The bone and teeth are usually real fossil material, but many jaws are repaired, partly sculpted, or have teeth from the same beds glued into the sockets. Some are composites from several animals. A real jaw is not the same as an unaltered jaw, so ask for a written restoration statement. Every jaw we sell is labeled natural, repaired or restored.
How does UV light help check a mosasaur skull?
Under a long-wave UV lamp, fossil bone and enamel fluoresce in a fairly even way, while modern glues, resins, paints and many fillers glow brighter, darker or in a different color. Restored areas and glued teeth often stand out clearly. UV does not catch every repair, but it is a quick, cheap first check.
Why are complete mosasaur skulls so rare?
Mosasaur skulls are made of many loosely joined bones that separated after death, and the phosphate beds are mined on a large scale, which breaks bones further. Finding a skull with its bones still associated is uncommon. That is why most skulls on the market are partly reconstructed and why fully natural examples command much higher prices.