Marbod of Rennes and the Liber lapidum, the most read lapidary

If an educated reader of the twelfth century wanted to know something about stones, he would very probably open Marbod's Liber lapidum. This Latin poem, written by a schoolmaster who became a bishop, enjoyed an extraordinary circulation: more than a hundred manuscripts are known, and it was soon translated into the vernacular languages. For centuries it was the standard text on the virtues attributed to gems, and many beliefs still repeated today go back, through him, to the lapidaries of late antiquity.

A master from Angers

Marbod was born at Angers around 1035 and for many years directed the cathedral school there, one of the liveliest cultural centres of western France. In 1096 he became bishop of Rennes, in Brittany, and in his last years he withdrew to the abbey of Saint-Aubin at Angers, where he died in 1123. He wrote religious poetry, lives of saints and secular pieces much admired by his contemporaries, who considered him one of the finest Latin poets of his time.

The Liber lapidum, probably written before his episcopate, belongs to this output of learned poetry. Marbod writes in hexameters, in a clear and regular style designed to be memorised and taught in schools, where the lapidary also served as an exercise in reading Latin. The poetic form partly explains its success: a list of virtues in verse was easier to remember than a prose treatise.

Sixty stones and an ancient frame

The poem describes about sixty stones, from diamond to agate, from emerald to coral. In the prologue a line declares the source: Evax rex Arabum legitur scripsisse Neroni, that is, Evax, king of the Arabs, is said to have written to Nero. Marbod thus takes up the tradition of Damigeron and Evax, which he had in Latin, and enriches it with information drawn from Pliny, Solinus and Isidore of Seville.

For each stone the poet gives its appearance, origin and traditional virtues. According to the lore he collected, agate makes its wearer pleasing, coral protects against storms, onyx brings sad dreams. Marbod does not present these qualities as his own discoveries but as an inheritance from the ancients, and places them within the Christian idea that God had put hidden virtues into stones, as into herbs and words.

Vernacular success

The poem's success was swift. As early as the twelfth century translations appeared in Old French and Anglo-Norman, followed by versions in Provençal, Italian and several other European languages. Many medieval vernacular lapidaries are in fact more or less free adaptations of Marbod, who thus became one of the main channels through which ancient knowledge about stones reached readers who did not know Latin.

Marbod was neither a naturalist nor a magician, but a poet and a churchman who gave elegant form to an ancient body of knowledge. His lapidary shows how the Christian Middle Ages received the late antique beliefs about stones, placing them within a vision of creation in which everything had a meaning. For anyone studying amulets it remains an indispensable source for understanding where many traditions about protective gems come from.