How to Identify Shark Teeth
Picture this: you are enjoying a peaceful stroll along a windswept British beach. The tide is low, the shingle is glistening, and then your eye catches something small, sharp, and distinctly dark among the pebbles. Could it be nothing more than a shard of shell? Perhaps a curious piece of sea glass? Or, just possibly, have you stumbled upon a tangible link to the Mesozoic or Cenozoic era—a fossilised shark tooth?
Finding a relic from one of the ocean’s most ancient and powerful predators is a thrill for any collector. This guide will transform your beachcombing from a casual wander into a targeted treasure hunt. We will equip you with the knowledge to reliably identify your findings, covering everything from the fossilisation process to the defining features that reveal the tooth’s original species.
Table of contents
- How do shark teeth fossilise?
- What to look for when you think you’ve found a shark tooth
- Where are you most likely to find shark teeth?
- How shark teeth are identified by species
- Get an expert opinion
- Discover fascinating shark teeth at Fossils UK
How do shark teeth fossilise?
The sheer abundance of shark teeth found worldwide is a testament to the animal’s rapid-fire dental system. Unlike humans, sharks constantly shed and replace their teeth, sometimes losing thousands in a lifetime. When a tooth drops to the seabed, the journey to becoming a fossil begins.
For fossilisation to occur, the tooth must be rapidly buried in sediment, such as mud or sand, before oxygen and bacteria can cause it to decompose. Over millions of years, water rich in minerals—often including iron, manganese, or phosphate—seeps into the porous tissue of the tooth, replacing the original organic material and calcified tissue (dentin) molecule by molecule. This process is called permineralisation.
Because of the minerals involved, the completed fossil rarely retains the creamy white of a modern tooth. Instead, a true fossilised shark tooth usually has a dark, rich colour. This can range from deep black or grey if high in phosphate, to earthy reds and browns if iron oxide is present. This mineral-rich composition is what gives fossil teeth their incredible density. It allows them to survive intact for millions of years.
What to look for when you think you’ve found a shark tooth
Identifying a potential shark tooth requires looking beyond the general shape and checking for four primary physical criteria.
| Feature | What to Look For | Why It Matters |
| Shape | Examine the crown’s outline. Most fossil teeth feature a distinct triangular or blade-like crown (the enamel part) set upon a wider, often bi-lobed root. Modern shells or pebbles may appear sharp, but they seldom possess this specific crown-and-root structure. | The specific geometry tells you if the object is dental in origin and what part of the jaw it came from (anterior teeth are long and slender; lateral teeth are wider and more angled). |
| Texture | Run your finger carefully over the tooth’s surface. The crown will feel smooth, hard, and vitreous (glass-like) due to its mineralised enamel layer. This contrast of texture between the smooth crown and the slightly rougher, denser root is a key indicator. | This distinct hardness and texture separate the tooth from common rock fragments or non-dental bone material. |
| Symmetry | Hold the tooth up. Does the blade point straight up from the root, or is it angled to one side? Teeth from the front of the jaw (anterior) are often symmetrical. In contrast, teeth towards the sides (lateral) are characteristically asymmetrical, leaning to the left or right. | Symmetry helps determine the tooth’s position in the shark’s mouth, which in turn aids species identification. |
| Serrations | This is the most crucial detail for identifying predatory species. Closely examine the crown’s cutting edges, sometimes with a magnifying glass. Serrations are tiny, saw-like jagged edges that sharks use to slice prey. Many ancient and extinct species, like the iconic Megalodon, possess these features. | The presence, size, and pattern of serrations often immediately narrow down the potential species. Non-serrated teeth are typically found in fish-eaters like the Mako or Sand Tiger sharks. |
Where are you most likely to find shark teeth?
You do not need to journey to far-flung continents to discover ancient shark teeth. The UK coastline offers fantastic opportunities for collectors. The best places are typically areas experiencing high coastal erosion, where the sea regularly exposes sediment layers dating back up to 55 million years.
Here are some of the most popular and productive sites in Britain:
- Beltinge (Herne Bay, Kent): Often cited as one of the country’s best locations for shark teeth, particularly after spring low tides. The erosion of the London Clay and Upnor formations frequently washes out teeth from prehistoric species, including the common Sand Shark.
- Bracklesham Bay (West Sussex): Located near Selsey, this beach is famous for its Eocene Bracklesham Group fossils. Simply sifting through the foreshore shingle at low tide can yield an excellent collection of ray plates and shark teeth.
- Walton-on-the-Naze (Essex): The cliffs here are composed of London Clay and the younger Red Crag formation. The continual erosion exposes countless fossils. While the majority are small sand shark teeth, the site is known for occasionally revealing the much-sought-after, though often worn, teeth of the giant extinct shark, Megalodon.
- Barton on Sea (Hampshire): The cliffs and foreshore along this stretch of coast are famous for the Barton Clay, which is particularly rich in Eocene-era marine fossils, including numerous species of shark and ray teeth that are easily found washed up on the sand.
How shark teeth are identified by species
Once you have confirmed your find is a fossil tooth, the real work of species identification begins. Experts use a combination of factors, primarily the tooth’s morphology (size and shape) and the presence of cusplets (small side points) or serrations. The tooth’s function is directly linked to the shark’s diet and species, making identification a form of palaeontological detective work.
Here is a guide to the defining characteristics of some common and historically significant fossil shark species:
| Species | Primary Shape | Key Features for Identification | Diet Indicated |
| Great White | Broad, triangular | Uniform, coarse serrations from tip to root base. No cusplets. | Large fish, marine mammals (slicing and cutting) |
| Mako Shark | Slender, needle-like | Highly conical and smooth blade. No serrations whatsoever. The root is often bulbous or bilobed. | Fast-moving fish and squid (piercing and gripping) |
| Sand Tiger Shark | Long, slender, recurved blade | Distinct, small cusplets (often two) flank the main crown. The blade is smooth (no serrations) and often curves inwards. | Small fish and crustaceans (spearing and holding) |
| Megalodon | Massive, robust, triangular | The largest teeth found. Distinguished by fine, distinct serrations and a chevron-shaped (V-shaped) nutrient line on the root. | Large marine mammals (ultimate cutting and crushing) |
| Tiger Shark | Short, squat, heavily curved | Distinct, deep notch where the crown meets the root. Coarse serrations run along the entire cutting edge, often appearing asymmetric. | Anything—especially turtles and shellfish (sawing and tearing) |
Get an expert opinion
While guides like this are excellent starting points for preliminary identification, the world of shark teeth is vast and includes many highly similar species. If you believe you have found a rare, unusual, or particularly well-preserved specimen, obtaining a professional opinion is the best course of action.
We strongly advise you to contact a local history museum, university research group, or a reputable geological society in your area. These experts have access to vast reference collections and the necessary knowledge to precisely date and classify your find. They can provide accurate scientific context and ensure your fossil is correctly recorded, which can be invaluable to research.
Discover fascinating shark teeth at Fossils UK
Identifying fossilised shark teeth is a truly rewarding pursuit that connects you directly with the deep, ancient history of our planet’s oceans. By focusing on the shape, the enamel’s telltale texture, and crucial features like cusplets and serrations, you can confidently identify your find.
Ready to see how some of the planet’s most magnificent predatory teeth look when professionally curated? Browse our complete range of shark tooth fossils at Fossils UK today.
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