Two hours from London on the border of Dorset and Devon lies the small seaside town of Lyme Regis. Since the Nineteenth Century the beach has attracted countless people, attracted by the treasure that can be found there. They come for the sea and sunshine, but also to hunt for the fossils that litter the area. The beach runs east to west in a wild sweep and it is as if you are moving through time as you walk along it. As you move from east to west the rocks get younger.
To the east at Black Venn is where local hero Mary Anning did much of her collecting but all parts of the beach on either side of town produce an abundance of fossils.
How to find fossils
Wherever you look for most people, it is pretty easy to discover the fossilised remains of ammonites. A little harder to find are belemnites and hardest of all, the fossilised remains of of giant ichthyosaurs and plesiosaurs that have remained undisturbed for 180 million years.
Who should hunt for fossils?
Children are often better than adults at fossil hunting. Younger eyes and being closer to the ground are both advantages that taller older people don’t possess. In fact, Mary Anning discovered Britain’s first complete ichthyosaur when she was just 12-years-old.
However, due to the tides, kids should never be left alone when hunting for fossils and should never be allowed to use rock hammers without eye protection and adult supervision. There are plenty of signs reminding people to stay away from the bottom of the cliff too. It isn’t just “health and safety gone mad”. The cliff face is very unstable and rockfalls are common so heed the warnings.
Why is Lyme such a good spot for fossil hunters.
It all comes down to geography. Firstly the rocks around the area are mostly sedimentary rocks. Sedimentary rocks are where most fossils are found. The light coloured limestone is the main rock type but there are bands of clay and shale rocks too. In fact the fossils in the softer shale and clay are more likely to be found in a complete, unbroken form.
Secondly the erosion of the beach is ensuring that new fossils are constantly being uncovered by the action of the tides and storms.
So, with plenty of fossils to find, if you want to find them you need to know what they look like. Lets start with ammonites.
Hunting for Ammonites
Between 240 – 65 million years ago sea creatures related to modern cephalopods (squid, octopus, nautilus and cuttlefish) roamed the oceans. their remains look very much like ribbed snailshells. There are tiny ammonites about 1mm in diameter and huge ammonites over a metre across. In all cases the ribbed shape is the clue and once your eyes are tuned in, it is these that you tend to find in abundance.
One of the nice things about hunting for ammonites is that you dont even need to bash rocks open to find them. When the stoms break open rocks and wash the fossils from the softer surround the smaller fossils tend to fall amonst the gravel and they stay there until someone picks them up. So, the best beginners low impact method for fossil hunting is simply to sit on a boulder by a patch of gravel and grab a handful and work your way through it.
If you are lucky (or spend more than half an hour doing this) you can find exquisite specimens in this way. If you especially blessed you may find a pyritised fossil. This is where lots of iron was included in the minerals that formed the fossil. You can end up with a stunning fossil that looks as if it has been metal plated, or in the right light, as if is made of gold.
Iron pyrite (fools gold) can also be found on its own and is worth looking out for. It shines beautifully in the sunlight and really does look like you have struck gold. Kids in particular will delight in an afternoon of trasure hunting.
All the beaches at Lyme have Ammonites, but some spots are better than others. Monmouth Beach to the west of town is where you can see boulders with some truly huge trace ammonites on them.
Hunting for Belemnites
Another extinct cephalopod, belemnites are preserved in the fossil record as small bullet or pencil shaped rods.
Monmouth Beach to the west of Lyme is a good spot for bullet-shaped belemnites in particular.
Hunting for ichthyosaurs and plesiosaurs
Alongside cephalopods the fossil record holds ancient shellfish (locally known as ‘devils toenails’ and the fossilised bones of larger marine reptiles such as ichthyosaurs and plesiosaurs.
On your first visit to Lyme Regis you may find quite a few confusing fossils. Is the one above a vertibrae of a marine creature or perhaps a holdfast for an ancient seaweed? Perhaps it is the remenant of a coral ancestor?
You will soon discover that finding things you dont fully understand yet is just as exciting as finding obvious fossils. The shops of Lyme sell books that will help make your next fossil hunting expedition even more rewarding than the last.