Snakestones

Myths, magic and legends

Before anyone knew what they were, people all over the world told stories about ammonites.

How this site works. Every fact is in our own words and linked to its source, beside it. Where good sources disagree, we show each version in a “Sources differ” box.

Snakestones

In England, ammonite fossils were called snakestones, because they look like coiled snakes turned to stone. NHM, snakestones

But ammonites weren’t reptiles at all. They were sea-dwelling molluscs. NHM

Snakestone stories came mainly from two places where ammonites are common: Whitby in Yorkshire and Keynsham in Somerset. NHM, snakestones

In his book Britannia of 1586, William Camden wrote that if you broke them open you found ‘stony serpents, wreathed up in circles, but eternally without heads’. NHM, snakestones

St Hilda of Whitby

In Whitby the legend goes back to Saint Hilda (614–680), the Saxon abbess who was to found an abbey there. She is said to have turned the town’s snakes to stone and thrown them off the cliffs. NHM, snakestones

The ammonite Hildoceras bifrons, one of the commonest at Whitby, is named after her. NHM, snakestones

Sir Walter Scott told the story in his poem Marmion: ‘Of thousand snakes, each one / Was changed into a coil of stone’. NHM, snakestones

Whitby’s coat of arms includes three snakestones. BGS

Some versions bring in St Cuthbert, a seventh-century monk said to have cast a beheading curse on the snakes, which explains why snakestones have no heads. NHM, snakestones

Keynsham and the fairies

In Keynsham the story is that St Keyna turned the serpents of the woods to stone by prayer. NHM, snakestones

Other stories said snakestones had once been fairies, turned into snakes and then into stone. NHM, snakestones

Horns of Ammon

Many ammonite names end in -ceras, from the Greek keras, meaning horn. BGS

Lyme Regis was especially rich in ammonites, then called ‘Ammon’s horn’, and in belemnites, the ‘devil’s fingers’. NHM, Mary Anning

Around the world

Ammonites have fascinated people since at least the Middle Stone Age, and have been found on every continent. NHM, snakestones

Ancient Romans believed that sleeping with a golden, pyrite ammonite from Ethiopia under the pillow could help you dream the future. NHM, snakestones

In Hindu culture, black stones holding ammonites are called saligrams, and are treasured because they look like the disc, or chakra, held by the god Vishnu. NHM, snakestones

True saligrams come only from the valley of the Gandaki River in Nepal and northern India. Sanskrit texts mention them over 2,200 years ago. NHM, snakestones

In Chinese folklore ammonites were Jiaoshih, horn stones, because they look like coiled rams’ horns. NHM, snakestones

The 11th-century Chinese scientist Su Sung described a ‘stone-serpent’ shaped like a coiled snake with no head or tail-tip, adding that nobody knew what animal had been turned to stone. NHM, snakestones

The Blackfoot people of North America called ammonites insikim, buffalo stones, because they look like sleeping bison, and used them in ceremonies to bring bison herds in. NHM, snakestones

It was believed buffalo stones could have babies, perhaps because ammonites tend to break apart along their septa. NHM, snakestones

In New Guinea, the Tifalmin people of the Upper Sepik River used ammonites as charms for hunting and farming. NHM, snakestones

Farmers in Germany’s Harz Mountains called them dragonstones, and put one in the milk pail to bring back a cow’s milk. NHM, snakestones

In parts of Scotland they were crampstones, used on cows with cramp. NHM, snakestones

Ammonites have been collected more than 5,000 metres above sea level in the Himalayas. NHM, snakestones

Myths, checked

1. MythAmmonites were snakes turned to stone.

   FactBut ammonites weren’t reptiles at all. They were sea-dwelling molluscs. NHM Ammonites were sea animals with shells: extinct cephalopods, the group that includes today’s squid, octopuses and nautiluses. NHM

2. MythSnakestones were found with their heads on.

   FactIn his book Britannia of 1586, William Camden wrote that if you broke them open you found ‘stony serpents, wreathed up in circles, but eternally without heads’. NHM, snakestones To back up the legend, and to sell them more easily, Victorians carved snake heads on ammonites. NHM, snakestones

3. MythAmmonites were basically nautiluses.

   FactA 2021 study of a rare fossil with soft parts found evidence that squid, octopuses and cuttlefish might be closer relatives of ammonites than had been thought. Imperial College The same study found muscles that nautiluses do not have, so ammonites and the nautilus may be less alike than was thought. Imperial College

4. MythAmmonites had lots of tentacles, like a nautilus.

   FactThe museum’s fossil curator thinks ammonites more likely had eight arms than the many tentacles of a nautilus. NHM No fossil of ammonite arms has been found yet, so much of what we know about the soft body is inferred from living cephalopods. NHM

5. MythThe animal filled its whole shell.

   FactThe animal lived only in the last chamber, the body chamber. The earlier chambers held gas or fluid, which it could adjust to rise, sink and move, much like a submarine. BGS

6. MythAll ammonites coil in a flat spiral.

   FactShells could be loosely or tightly coiled, flat or twisted like a corkscrew, and some started as a tight spiral and then straightened out. NHM Nipponites mirabilis, found in Japan, is exceptionally rare and looks a bit like a knot. NHM

7. MythAmmonites lived in the deep ocean.

   FactThe Natural History Museum says they tended to live in shallower seas, perhaps down to about 400 metres. NHM The British Geological Survey says they could probably not cope with depths of more than 100 metres. BGS

8. MythEvery ammonite died out in the same instant as the dinosaurs.

   FactNot quite all went at once: a few species lived on into the Palaeogene in the Western Interior Seaway before dying out. NHM

9. MythAmmonites are rare fossils.

   FactThey died out about 66 million years ago, and their fossils turn up all around the world, sometimes in huge numbers. NHM Ammonites are among the commonest fossils on the Dorset coast, so ordinary finds don’t need recording, though unusual species or very large shells are worth recording. West Dorset Code

10. MythYou can take any ammonite you find on Monmouth Beach.

    FactBut visible water-worn ammonites, especially on Monmouth Beach, must be left, and the ammonite pavement must not be damaged. Undercliffs Code

11. MythThe film Ammonite is the true story of Mary Anning.

    FactThe 2020 film Ammonite, with Kate Winslet as Mary, is not a biopic: its director says so. BBC News