Some of my favourite jewellery is made from Turbinidae, turban snails, a family of marine gastropod molluscs. These molluscs have external shells, shaped like a turban, which are big enough for the soft body of the mollusc to withdraw completely into it. Some of these molluscs have a trapdoor that they shut to keep out predators. When in use, the trapdoor is flexible but it hardens when the shell is no longer occupied. It is this trapdoor on turban shells, known as an operculum, which is turned into jewellery.
The opercula from Turbo petholatushave lovely circles of green and orange on a white background. They are sometimes called ‘cat’s eyes’. They are the most commonly used ones. The Astralium calcar and the L. smaragdus show similar colouring but are mainly green and white. The Bolma rugose is mainly orange while there are a few, like the Prisogaster niger, which are a creamy light gray, and the Astraea heliotropium and the Guildfordia yoka which are white.
The turban shells can be located in many different tropical areas including from the Caribbean, Australia, around South Australia, as well as temperate areas such as Japan and New Zealand. The Bolma rugose is found in the Mediterranean, near Portugal and the Canary Islands.
Some opercula jewellery was set in a base metal, but some was set in silver and gold. All of the pieces in the photographs are set in gold.