The cliffs at Blue Anchor contain a thin Triassic bone bed from the Rhaetian Penarth series. This is full of reptile, shark, and fish remains, similar to Aust on the River Severn. There are plenty of blocks to split. Jurassic ammonites and reptile bones are also frequently found here.
DIRECTIONS
♦ From the A39, take the B319 or the road from Bilbrook through Old Cleeve to Blue Anchor. Please note, forma access from the B3191, which runs between Watchet and Minehead is now permanently closed to cars due to erosion. Park at the most Eastern side along the promenade and walk east towards Watchet.
♦ On a good day and tides permitting, you can walk from Watchet to Blue Anchor and back. However, the tide can reach very high up the beach at some points and you can be completely cut off. So be careful and make sure you allow plenty of time to get back if you choose this route.
♦ A ramp gains access to the foreshore from the promenade, but is only accessible around three hours after high tide. And this can quickly become cut off soon after low tide.
♦ Postcode to main parking area: Postcode: TA24 6JR
♦ What3Words to the main collecting site: ///cashiers.cactus.indulgent
DOWNLOAD THE UKF BOOKLET TO FOSSIL HUNTING AT BLUE ANCHOR
VIDEO FILM
PROFILE INFO
FIND FREQUENCY: ♦♦♦ – Blue Anchor is very productive but you have to work for your finds. You will need a good hammer and chisel, as the bone bed is very hard. Search the foreshore for rocks from the bone bed and split these finely. It is also recommended to take samples home and use very small chisels to break them into small pieces. You will be surprised how rich this bed is for teeth.
CHILDREN: ♦♦♦ – As the rocks are very hard, fossils within the bone bed will require heavy hammers to extract. Therefore, this location is not suitable for young children.
ACCESS: ♦♦♦♦ – Access to the beach at Blue Anchor is easy. Park along the seafront and walk down to the beach by means of the concrete slipway.
TYPE: – Blue Anchor is a cliff and foreshore location, although fossils are only really found within the rocks from the bone bed, which can be found scattered along the beach. At the Blue Anchor headland, where you will see some very large rocks, all the beds going eastwards are Jurassic and are covered in our Watchet guide.
FOSSIL HUNTING
Small bones are very common at Blue Anchor, including many fish remains, teeth, spines, small bone fragments and vertebrae. In fact, the fossiliferous Westbury Beds are packed with fish remains. There is also a huge variety of small bones found here, but getting them out and getting them home is a completely different story. It may be easier to look for smaller blocks around the foreshore instead of trying to get bones out of the hard larger blocks, unless you have the right equipment.
The red Triassic cliffs do not contain any fossils, so you will need to walk towards the start of the grey cliffs. At Blue Anchor Point, blocks of bone bed can be seen on the foreshore. Some of these can be huge. Search around these blocks and look for any interesting bones. Once you find a good block, it can take a long time to split it into small pieces. Alternatively, you can take some samples back home for further splitting. Sometimes, nodules can be found that contain larger bones. These tend to be found in sandy pockets together with giant limestone nodules.
GEOLOGY
Blue Anchor Bay (Somerset coast, UK) is a classic place to see the latest Triassic rocks passing up into the earliest Jurassic. Here, the Blue Anchor Fault juxtaposes Jurassic strata against the Triassic marls of the Mercia Mudstone Group, creating an abrupt change in rock type and fossil content along the bay.
The foreshore and low cliffs expose a condensed but highly informative succession spanning the Middle–Upper Rhaetian (Late Triassic) into the Lower Jurassic (Lias Group). The sequence is easiest to understand if you read it from top to bottom (youngest to oldest), noting the repeated alternation of mudstones, shales, and limestone beds that reflect rapid environmental shifts in a shallow sea.
Stratigraphy (top to bottom)
- Blue Lias Formation – the highest beds at Blue Anchor, typically thin limestones interbedded with darker laminated shales. These represent the earliest Jurassic “Lias” seas and often show strong bed-to-bed changes (hard limestone ledges alternating with softer shale). At Blue Anchor, the Blue Lias rests sharply on an irregular surface cut into the Cotham Member mudstones and the pale, fine-grained Langport Member (“White Lias”) limestones below. Together these units mark a key transition interval close to the Triassic–Jurassic boundary.
- Westbury Formation – famous for fossil-rich horizons. At the very top is the Basal Bone Bed. Below, a ~6.4 m interval of dark, fossiliferous shales with thin (often nodular) limestone beds reflects quieter-water conditions with abundant organic material. Occasional sandstones occur in the lowest ~1.2 m. Larger bones can occur but are generally less common. A distinctive mid-section includes the Ceratodus Bone Bed, followed by a gritty bed with fish remains resting on a thin, ripple-marked sandstone—often the most sought-after horizon for collectors.
The upper part of the Westbury Formation transitions into a ~7 m bed that begins with thicker limestones containing common marine fossils such as Rhaetavicula contorta, Chlamys valoniensis, Tutcheria cloacina and Eotrapezium concentricum. Up-section, these beds become more shale-rich, with the final ~1.65 m dominated by shales. This limestone-to-shale shift is a useful visual marker of changing seafloor conditions (from better-oxygenated carbonate deposition to muddier, lower-energy sedimentation).
- Blue Anchor Formation (Mercia Mudstone Group) – mainly grey-green and yellow marls that form much of the cliff exposure. These mudstones record a more restricted, often evaporitic coastal setting compared with the fully marine beds above.
Faulting, features, and what to look for
Toward the eastern end of Blue Anchor, the fossil-bearing succession is abruptly replaced by older Triassic marls that are typically poorly fossiliferous. This sudden change is caused by displacement along the Blue Anchor Fault, which brings contrasting rock packages side-by-side. If you’re walking the shore, you can often spot the difference immediately: richly bedded shales/limestones on one side versus softer, more uniform marls on the other.
One of the most striking visual aspects of the Blue Anchor Formation is the alternating grey and green mudstones, commonly containing nodular gypsum (white to pink; locally “alabaster”). These gypsum nodules formed during evaporation in restricted conditions and are a hallmark of the late Triassic marginal environments preserved here.
- Textures & structures: look for ripple-marked sandstones, nodular limestone beds, and sharp bedding contacts that mark rapid shifts in sea level, sediment supply, and oxygenation.
- Fossil horizons: bone beds and gritty fish-bearing layers in the Westbury Formation can be laterally variable—systematic searching of freshly fallen blocks often produces the best results.
- Field safety: cliffs can be unstable and tides move quickly—plan around low tide, keep distance from cliff faces, and avoid working directly beneath overhangs.
ACID PREP
The Blue Anchor bone bed (often referred to as part of the Rhaetian bone-bed horizon within the Westbury Formation) is typically a thin, locally patchy layer formed as a high-energy lag deposit when the sea advanced over older Triassic mudstones. Rather than preserving fossils neatly “in place,” it commonly concentrates tough, durable material: vertebrate teeth and bone fragments, fish debris (scales, denticles), phosphatic pebbles, small clasts ripped up from underlying mudstones, and occasional shell or limestone fragments.
That mix is exactly why acid-based preparation can be useful for this bed: the cement and matrix are often carbonate-rich, while many of the collectible microfossils (especially the smaller vertebrate elements) are more phosphate-rich and can survive careful, controlled chemical prep better than the surrounding carbonate.
What acid prep is best for (and what it isn’t)
Acid prep is usually most effective here when your aim is bulk recovery—freeing lots of small, isolated fossils for sorting—rather than producing a single “display specimen.” Bone-bed material is commonly reworked and fragmentary, so the payoff is often in the microfossils you can’t easily extract by hand.
A practical, non-technical workflow overview
It helps to frame acid prep as “lab-style processing” rather than a quick trick.
- Start by understanding your matrix. A small test on non-valuable matrix can tell you whether the rock is likely to respond (carbonate-rich material reacts readily; clay-rich material may not).
- Work in controlled cycles. Short exposures with long rinses between them are generally safer than prolonged soaking, because they reduce the chance of softening or etching fossil surfaces.
- Rinsing matters as much as the acid. Bone-bed residues can trap dissolved salts; if those salts crystallise during drying they can crack or flake delicate pieces. Thorough rinsing and patience reduces this risk.
- Expect a lot of “non-fossil” residue. Because the bed is a lag deposit, you’ll often process plenty of pebbles and mudstone clasts along with the fossils. The real results come from sieving and careful picking under magnification.
- Fragile pieces may need stabilising. Small bones and teeth can be porous or fractured; some collectors use suitable consolidants (applied sparingly) to help pieces survive handling and drying.
Common pitfalls with Blue Anchor bone-bed material
- Over-prepping: Rushing the process can leave fossils chalky, etched, or weakened—even if they don’t fully dissolve.
- Hidden weak spots: Some fossils look solid until they dry, then split along old cracks. Gentle handling and slow drying help.
- Iron sulphides (pyrite): Dark, organic-rich horizons can contain minerals that cause long-term deterioration if stored damp or sealed without care. Keeping material dry and well-ventilated after proper rinsing is important.
Safety note
Even “mild” acids are hazardous. If you choose to do chemical preparation, treat it like proper chemical handling: use appropriate eye/skin protection, good ventilation, acid-safe containers, and follow local rules for neutralisation and disposal. If you’re not set up for safe chemical work, stick to mechanical preparation and selective collecting.
SAFETY
Common sense when collecting at all locations should always be used and tide times should always checked before visiting. You can easily be cut off by the tide at Blue Anchor, as the sea reaches the cliff, especially round the first headland. You can walk to Watchet from here, but you should ensure you have left enough time for your return or to reach your destination. Care must be taken when splitting, hitting and breaking these rocks, as rock splinters can penetrate the body, especially the eyes. Therefore, you should always wear safety goggles. When using chisels, care must be taken to prevent breaking fingers or damaging hands.
EQUIPMENT
Many fossils can simply be collected from the fragments of bone bed along the foreshore, especially along the tide line. However, any large boulders from the bone bed will require strong tools to break them. The bed is so hard that splitting it is almost impossible unless a natural fault line or crack can be found. You will need a heavy hammer, chisels and safety goggles.
CLEANING AND TREATING
Begin by removing any loose sediment very carefully using a soft toothbrush. Take your time, as many fossils—particularly pyritic specimens—are fragile and easily damaged. Once cleaned, fossils should be desalinated by soaking them in fresh water for at least 24 hours to remove residual salt. After soaking, allow specimens to dry naturally at room temperature. Do not dry them on radiators or other heat sources, as rapid drying can cause cracking or long-term damage.
Once fully dry, we recommend sealing fossils with Paraloid B-72, dissolved in acetone. This is a museum-grade consolidant that is widely available in pre-mixed bottles. Paraloid B-72 is stable, long-lasting, and does not yellow or react chemically over time. Importantly, it is also fully reversible, making it suitable for scientifically important or display-quality specimens.
ACCESS RIGHTS
This site is an SSSI. This means you can visit the site, but hammering the bedrock is not permitted. For full information about the reasons for the status of the site and restrictions please download the PDF from Natural England – SSSI Information
It is important to follow our ‘Code of Conduct’ when collecting fossils or visiting any site. Please also read our ‘Terms and Conditions‘
LINKS
♦ Fossil Discussions
♦ Fossil Articles
♦ Buy Fossils, Tools and Equipment
♦ Buy Crystals, Meteorites, and Artefacts
♦ Join Fossil Hunts
♦ UK Fossils Network
