Shells can often be found on at pinnacle of headstones. They form a nice decorative piece like acanthus leaves, but they can also have symbolic meanings.
A shell was sometimes used to pour water in baptisms, so is an accepted Christian symbol. The shell on a headstone could also indicate that the deceased had found or rediscovered their faith recently.
In medieval times, a penance issued by priests could be a pilgrimage to St James’ shrine in Spain. To prove that they had completed the journey, a scallop shell would be collected from the beach nearby. From this, the shell became a symbol for all pilgrimages. As a pilgrimage is a personal journey to encounter God, the ultimate journey of all Christians is that from Earth to Heaven.
During the Jacobite uprisings in the early 18th century, the supporters of King James used secret symbols to identify their alliances. One of these was a scallop shell, as it was the symbol of St James and also of their ally Catholic Spain. The photo showing a scallop shell on a headstone from the early 18th century, was taken close to the Scottish border. Could those swirls represent a fleur-de-lys, the symbol for Catholic France?