Composed of a fossilised sea urchin, mounted within a yellow gold mount, small aperture to the reverse, rounded shank, mounted 16th/17th century. EU ring size 56. US ring size 8. UK ring size P. Total weight: 9.61 grams

Gemstones being imbued with magical characteristics is something that is documented since the ancient world, and known to have been part of human life since pre-history. And not - as perhaps now, in our science-led society - as niche as you might think. Worn by different echelons of society to ward off or encourage almost any eventuality you can think of, gems and found objects of all varieties were a common way of seeking understanding and agency over the twists and turns of life. And fossils, in the pre-Darwinian world, were glorious food for the imagination in this regard.

More common than the use of fossilised sea urchins (or Echinoids, to use their proper name) in jewellery, there is mention of magical 'toadstones' as early as Pliny the Elder in the 1st Century AD. Thought to protect against most evils and ailments - from poison to dropsy to sinking ships - these shiny domed brownish-coloured "gems" were so-called as they were believed to be harvested from the heads of live toads. In fact, they were the fossilised teeth of an extinct fish that lived during the Jurassic and Cretaceous periods.

Fossilised sea urchins' distinctive shape and five-armed star decoration seem to have caught the eye of even more distant ancestors. These rather beautiful specimens can be found strategically placed in graves and (more rarely) used in jewellery since prehistory (there is evidence of them having been prized by even Neolithic Homo heidelbergensis 400,000 years ago).

Sometimes referred to as sugar loaves or fairy loaves, snake eggs (these too appear in Pliny the Elder's writings), thunder stones, pound stones, shepherd's crowns...to name but some of the English iterations. All with significances and uses particular to the association. Echinoids' symbolic and talismanic qualities evolved down the generations and travelled far and wide. For example, there's a rather telling folkloric mirroring between Southern England and Denmark where they were thought to predict a thunderstorm by sweating, stop milk from turning and, (more significantly) as protectors against evil. In both locations they were placed outside houses (evidence of this can be found in the windows of a church in Hampshire, dating to the 12th century). One can only presume this similarity was propagated by Viking invasions. The placement of these echinoids outside homes was documented as still being a practice in Suffolk in the early 20th Century, although rather more loosely done for the sake of tradition and the idea that they brought good luck.

The echinoid as a protective force is one of its most resonant themes in its interpretation by mankind, and potentially the inspiration for this particular ring. It is mounted as the toadstones of the 16th and 17th Century were, with a small aperture to the reverse of the stone to bring it closer to the wearer’s skin. A practice popular with toadstones in the 16th & 17th Centuries as they were thought to detect poison and start sweating. Whatever this ring’s original imagined power, it has one that endures to today, the power to evoke wonder and curiosity.