Pliny the Elder & Gemstones: Natural History Guide

The Roman Who Catalogued the Gem World

Among all the ancient writers who engaged with the world of precious stones, none left a more comprehensive, more influential, or more entertaining account than Gaius Plinius Secundus — Pliny the Elder — the Roman administrator, military commander, and encyclopaedist whose Natural History, completed in 77 CE and dedicated to the emperor Titus, is the most ambitious work of natural science produced in the ancient world and the primary source of our knowledge of Roman gem culture. Pliny's Natural History, which runs to thirty-seven books and covers the entire range of the natural world from astronomy and geography to zoology, botany, and mineralogy, devotes three books — Books 33, 36, and 37 — to the description of metals, stones, and gemstones, providing the most comprehensive ancient account of gem materials and their properties, origins, and uses that has survived from antiquity.

Pliny the Elder was not a professional scientist or philosopher but a man of extraordinary intellectual curiosity and encyclopaedic ambition who devoted his considerable administrative talents and his prodigious capacity for work to the compilation of a comprehensive account of the natural world and its products. His Natural History, which he described as a work of thirty-seven books, twenty thousand facts, and two thousand volumes consulted, was the product of a lifetime of reading, observation, and inquiry, and it reflects the Roman world's characteristic combination of practical empiricism with a deep engagement with the philosophical and cosmological dimensions of natural knowledge. Pliny died in 79 CE during the eruption of Vesuvius that destroyed Pompeii, killed while attempting to observe the eruption and rescue survivors — a death that was entirely in keeping with the spirit of insatiable curiosity that animated his life's work.

Pliny's Gem Methodology

Pliny's approach to gemstones in the Natural History combines several different methodological approaches that reflect the diverse sources on which he drew and the diverse purposes that his gem accounts were intended to serve. His primary approach is descriptive and encyclopaedic, providing systematic accounts of the physical properties, geographical origins, and commercial values of specific gem materials that reflect his extensive reading in the Greek and Roman gem literature and his own observations of the Roman gem market. He also incorporates mythological and historical anecdotes about specific gems and gem-related events that reflect the Roman tradition's characteristic combination of natural history with cultural history, and he provides practical information about the detection of gem forgeries and the assessment of gem quality that reflects the concerns of the Roman gem market.

Pliny's gem accounts are particularly valuable for the information they provide about the commercial values of specific gem materials in the Roman market, as he frequently notes the prices paid for exceptional gems and the relative values of different gem materials in the Roman luxury market. His account of the pearl earrings of Cleopatra, which he values at ten million sesterces each — an almost incomprehensible sum by any standard — is one of the most famous passages in ancient literature about the value of precious stones, and it provides important evidence of the extraordinary prices that the finest gem materials commanded in the Roman luxury market. These commercial valuations, combined with Pliny's descriptions of the physical properties and geographical origins of specific gem materials, make the Natural History an invaluable source for the economic history of the Roman gem trade.

Pliny on the Diamond

Among the most important and most influential sections of Pliny's gem books is his account of the diamond — the adamas — which he describes as the most precious of all gem materials and the most powerful of all natural substances. Pliny's account of the diamond reflects the ancient world's understanding of the stone as a material of extraordinary hardness and cosmic power, capable of resisting any force and of cutting any other material. He notes the diamond's extraordinary hardness, its ability to resist fire and iron, and its use as a tool for engraving other gemstones, providing an accurate account of the stone's most important physical properties while also reflecting the ancient tradition's understanding of the diamond as a material of divine invincibility.

Pliny also describes the ancient belief that the diamond could neutralize the effects of poison and protect its wearer from madness and other harmful influences, reflecting the ancient gem healing tradition's understanding of the diamond's extraordinary physical properties as expressions of a cosmic power that extended to the protection of human health and well-being. These healing associations of the diamond, which Pliny records without necessarily endorsing, established important precedents for the subsequent Western tradition's understanding of the diamond as a stone of protection, clarity, and invincible strength that continues to resonate in the modern world's appreciation of diamonds as the most powerful and most prestigious of all gemstones.

Pliny on Emeralds and Colored Stones

Pliny's accounts of colored gemstones are among the most detailed and most informative in the Natural History, reflecting the Roman world's extraordinary passion for vivid color in gem materials and the wide range of colored stones available through the Roman gem trade. His account of the emerald is particularly detailed, noting the stone's vivid green color, its soothing effect on the eyes, its occurrence in Egypt and other locations, and the various methods used to assess its quality and detect imitations. Pliny's famous observation that the emperor Nero watched gladiatorial combats through an emerald lens reflects the Roman imperial tradition's extraordinary passion for emeralds and the belief in the stone's beneficial effect on the eyes.

Pliny's accounts of other colored stones — including rubies, sapphires, amethysts, and a wide range of other gem materials — provide important evidence of the range of gem materials available in the Roman market and of the Roman world's sophisticated understanding of gem quality and gem value. His descriptions of the methods used to detect gem forgeries — including the use of glass paste imitations of natural gemstones — reflect the Roman gem market's awareness of the problem of gem fraud and the practical measures taken to address it, and they provide important evidence of the sophistication of the Roman gem trade's commercial practices. Pliny's Natural History thus remains, nearly two thousand years after its composition, one of the most important and most informative sources for the history of gemstones and gem culture in the ancient world.

Pliny's Healing Gem Tradition

Pliny's Natural History also provides extensive accounts of the healing properties of specific gemstones, drawing on the Greek and Roman medical traditions to compile a comprehensive catalogue of gem medicines and gem amulets that reflects the ancient world's sophisticated understanding of the therapeutic potential of precious stones. His accounts of gem healing properties combine empirical observations of therapeutic effects with mythological and philosophical explanations of the cosmic forces that gave specific stones their healing power, creating a rich synthesis of natural history and medical knowledge that would influence the subsequent development of Western gem medicine for more than a thousand years. The medieval lapidary tradition, which flourished in the twelfth and thirteenth centuries and which provided the theoretical framework for gem medicine through the Renaissance, drew extensively on Pliny's Natural History as one of its primary sources, transmitting the Roman gem healing tradition to the medieval and Renaissance worlds and establishing the foundations of the Western gem healing tradition that continues to resonate in the modern world's appreciation of crystals as materials of healing and spiritual well-being.