Fossil Coast Drinks is pleased to introduce Steve Snowball as a guest blogger who will be sharing his knowledge, experience and expertise in a series of blogs about fossil hunting at Black Head near Osmington Mills in Dorset along the Jurassic Coast. Steve is an accomplished author of "A Guide to Fossil Collecting in England & Wales" and co-author of a series of four other highly-acclaimed guides to fossil collecting on the Dorset coast.
The section of beach below Black Head can be accessed by a number of routes. For those who don’t mind an arduous walk, over quite rocky terrain, the coastal path that runs behind The Smuggler’s Inn at Osmington Mills, will enable access onto the beach, from which a walk westwards, towards Weymouth, will take you to the spot.
Alternatively, walk from Bowleaze Cove, heading east along the South West Coast Path (and taking in the lovely scenery) before reaching PGL Osmington Mills. From Osmington Mills, take the South West Coast Path but walk west to the PGL activity centre. From either direction, the metal steps below the PGL site will take you to the beach. PGL Osmington Mills is at DT3 6EG.
The somewhat tired looking cliff at Black Head has, of late, been rejuvenated by local storms and inclement weather, causing a significant slump of the clay and much material falling or slipping onto the breach. It is unwise to attempt to climb up or over the slipped material, as the clay can easily hide mud slides beneath the surface.
This is a dangerous and quite isolated part of the Dorset coast, so ensure that you have carefully checked tide times prior to setting out, wear appropriate clothing and footwear and tell someone where you're going and what time you're expecting to return. Mobile phone signals are not always available at this remote site!
Once at beach level, begin to examine the fallen material. During the latter part of 2024, a great deal of bone material has been found, including those from marine crocodiles, plesiosaurs, pliosaurs and ichthyosaurs.
Finding such vertebrate material is not common but not impossible. If you are fortunate enough to find any fossilised bone or teeth, it’s essential that you desalinate the fossils by initially soaking in fresh water (to remove any salt from the fossil) and then let it dry naturally, not on a radiator!.
Once dry, it’s a good idea to treat the fossil to a coating of Paraloid B-72. This is a product that will penetrate the bone and prevent any decay or future deterioration. use very thin solutions of Paraloid B-72 to consolidate or impregnate rocks and fossils, essentially turning them to plastic.
It used to be that Paraloid came only in powder form, which needed to be mixed with acetone. However, pre-mixed solutions are available from ZOIC Palaeotech ready to use straight out of the bottle and highly recommended.
The complex geology along this section of coast provides evidence of the Weymouth anticline: a huge dome-shaped structure, formed by the effect of earth movements that built the Alps some 20 million years ago.
However, the Lower Kimmeridge Clay here is aged around 154 million years and non-vertebrate fossils of marine origin are plentiful and include bivalves, brachiopods, worm tubes and gastropods.
Fossils At Black Head
Ammonites, or partial sections of ammonites, are found with some frequency.
The fossils above include Left: Rasenia cymodoce | Centre: Pictonia densicostata and Ringsteadia pseudocordata | Right: Amoeboceras sp. ammonites in calcite.
The Lower Kimmeridge Clay is characterised by the presence of the large oyster, Deltoideum delta which is a very common fossil at this location. These examples are only a representation of the gastropods and bivalves found in the Kimmeridge Clay at Black Head.
The fossils above include left: Palates of the fish Gyrodus cuvieri | Centre: Gastropods Bathrotomaria reticulata and Torquirhynchia inconstans | Right: Large oyster, Deltoideum delta
Vertebrate Fossils
Fossil bone is not uncommon at Black Head. Identification of isolated bone fragments is usually very difficult but much easier if the bone is that of a vertebra of a marine reptile. Below: Pliosaurus sp.
There is no evidence to conclusively prove for certain that bones and teeth found at this site are those of the Pliosaurus kevani, although only the skull was initially extracted from the cliff, along with the numerous bones found along the beach. However, teeth of a Pliosaurus kevani are found here.
As with any fossil collecting trip, luck will play a certain part as to what is available on the day. The most ideal conditions at coastal sites follow rough tides, where fresh falls or slides can reveal more fossils. However, the winter storms and relentless rainfall of the winters of 2023 and 2024 has meant the cliffs along much of the Jurassic Coast have become increasingly unstable.
White Nothe is no exception and whilst several rockfalls have occurred here, you should remain vigilant at all times. It will be much safer to avoid standing too close to the cliff face. It would also be very prudent to wear a safety helmet at this location. Traversing the rocky shore can be difficult and it’s easy to trip or fall over. A safety helmet is cheap to purchase (less than £10 in many hardware stores) and is a sensible piece of kit to own.
There will be ample material on the beach and from which fossils can be found. It’s best to coincide your visit with a falling tide. If the tide has already begun to rise upon your arrival then collecting will be confined to a limited area and time. Give yourself plenty of time for the return journey. It’s all too easy to lose track of the time and tides will undoubtedly cut you off.
About Guest Blogger - Steve Snowball
Steve Snowball spent a total of 35 years working in education; initially as a teacher, then as a headteacher and finally as an education advisor in West Sussex. He retired to live on the Jurassic Coast of West Dorset, where he was able to pursue his keen interest in collecting fossils and spending time walking his dogs, enjoying landscape photography, oil painting and gardening. Steve is the author of ‘A Guide to Fossil Collecting in England & Wales’ and co-author of a series of four other highly-acclaimed guides to fossil collecting on the Dorset coast, all published by Siri Scientific Press.