Pliny the Elder and the book of gems in the Natural History

Almost every history of protective stones passes, sooner or later, through Pliny the Elder. Born at Como in AD 23 or 24 and killed in 79 during the eruption of Vesuvius, while in command of the fleet at Misenum, Pliny was an officer, an imperial official and a tireless reader. His Natural History, dedicated to the future emperor Titus in 77, gathers in thirty-seven books the natural knowledge of the Roman world. The last book is devoted entirely to gems, and closes with a eulogy of Italy as the land richest in every natural good.

An encyclopedia of books and reports

Pliny states in the preface that he drew on a great many authors, and in the first book he lists the sources used for each of the following ones. His method is compilatory: he reports what he has read, often adding personal observations, prices, anecdotes and moral judgements. Books thirty-three to thirty-seven deal with metals, pigments, stones and gems, and form the main ancient source on these subjects.

In the thirty-seventh book hundreds of names of stones file past, many of which can no longer be identified with certainty. Pliny describes their colour, origin, imitations and commercial value, and gives space to famous stories: the ring of Polycrates, tyrant of Samos, which according to Herodotus was thrown into the sea and found again in the belly of a fish, or the agate of Pyrrhus with its natural image of Apollo and the Muses.

Scepticism towards the magicians

A trait that surprises the modern reader is Pliny's distrust of the promises of the magi, the term he uses for the sages of eastern tradition and their followers. Again and again he reports the virtues they attribute to stones only to distance himself from them, accusing them of lying or vanity. At the beginning of the thirtieth book he sketches a brief history of magic, which he calls the most deceitful of the arts.

This does not mean that Pliny was free of beliefs. He accepts many traditional opinions, and his work is full of reports we now consider groundless. But his attitude shows that already in the ancient world there was a distinction between learned tradition, which recorded customs and opinions, and the claims of professional magicians, who promised sure effects to those who paid them.

The medieval legacy

The Natural History was copied throughout the Middle Ages and became the basis of many later works. Solinus drew from it, in the third century, a widely read collection of marvels, Isidore of Seville, in the sixteenth book of the Etymologies, took over much of its information on stones, and the lapidaries of Marbod and Albertus Magnus preserve many traces of it. With the invention of printing the work had its first edition in Venice in 1469.

Reading the book of gems today means entering the workshop of a Roman scholar trying to put the world in order. Pliny does not always distinguish between observation and legend, but he preserves an extraordinary quantity of names, customs and stories. Without him much of the ancient history of stone amulets would be lost, and many beliefs of the following centuries would be incomprehensible.