Jet: the black stone from Whitby to Santiago de Compostela

Jet, azabache in Spanish, is a type of compact lignite: fossil wood transformed over millions of years into a black, light material that takes a high polish. Although not a mineral in the strict sense, it was always treated as a precious stone. Its deep colour and its ability to build up static electricity when rubbed, like amber, made it one of the most widely used amulets in Europe, particularly against the evil eye.

Pliny's gagates and the testimony of Bede

Pliny the Elder, in the thirty-sixth book of the Natural History, calls this stone gagates, after a place and a river in Lycia, in Asia Minor. He reports that when burned it gives off a smell believed to drive away snakes, and records other popular beliefs, including its use by magicians for a form of divination. As so often, Pliny records these notices without making them his own.

Centuries later the monk Bede the Venerable, at the beginning of his Ecclesiastical History of the English People, completed in 731, lists jet among the riches of Britain and repeats that its smoke puts serpents to flight. The stone was mined above all on the Yorkshire coast, near Whitby, and was already worked in Roman times at Eboracum, today's York, where numerous pendants and bracelets have been found.

The azabache of the pilgrims

In Santiago de Compostela, from the late Middle Ages, jet workers known as azabacheros formed a guild that produced images of Saint James, scallop shells and small amulets sold to pilgrims. The raw material came largely from Asturias. These objects, carried home to every part of Europe, combined the devotional memory of the journey with the protection attributed to the black stone. The jet shells and figurines found far from Galicia now help historians trace the routes of medieval pilgrimage.

In the Iberian Peninsula and Spanish-speaking America, the azabache fig, a small closed hand with the thumb pressed between the index and middle fingers, was hung on newborns to protect them from the evil eye. The custom has been documented for centuries, appears in seventeenth-century portraits of children of the Spanish court and still survives as a family tradition in some regions.

The black of Victorian mourning

In the nineteenth century jet enjoyed a new season of great popularity. After the death of Prince Albert in 1861, Queen Victoria wore mourning for the rest of her life, and the court adopted sober black jewellery. The Whitby workshops, which employed hundreds of workers, produced brooches, necklaces and lockets for mourning, sometimes with small compartments to hold locks of the deceased's hair.

Jet thus runs through European history with surprising constancy: from the beliefs recorded by Pliny and Bede to the souvenirs of the pilgrims of Compostela and the jewellery of Victorian mourning. In every age the black of the stone was associated with defence, recollection and memory. Its virtues belong to tradition, but the workshops of Whitby and Santiago have left artistic testimonies of great value.