Paradise Bejewelled: The Gems of Dante’s Divine Comedy

By Ann C. Pizzorusso

Dante’s writings reveal some hidden talents, such as his in-depth knowledge of gems.

This year we commemorate the 700th anniversary of the death of Dante Alighieri (1265–1321), best known for his Divine Comedy (Divina Commedia), penned between 1308 and 1321. The work was revolutionary in that it was the first book to be written in Italian, known as the Florentine Vulgare rather than Latin, which was the language of the elite. Although inspired by Homer’s great epic poems and Virgil’s Aeneid, Dante’s Divine Comedy chronicles a personal journey—his spiritual pilgrimage through the realms of Hell (Inferno), Purgatory (Purgatorio), and Paradise (Paradiso).

The poem overflows with insightful observations on the political and ecclesiastical upheaval that engulfed Dante’s native Florence in the Middle Ages. It presaged the nascent intellectual rumblings that would later become the Humanist movement and influenced the works of Francesco Petrarca, “Petrarch” (1304–1374), Giovanni Boccaccio (1313–1375) and Leonardo Bruni (ca. 1370–1444).


Even today, the work has also attracted scientists looking for insight into the state of “scientific knowledge” in the early 1300s, particularly the poet’s comments on physics and astronomy. Dante understood the spherical nature of the Earth, the placement of landmasses upon it, the differing stars in the southern hemisphere and the nature of meridians. With all this scholarly inquiry, however, there remains yet another area worthy of note.  That is Dante’s vast knowledge of gems and the emerging field of gemology.

Dante, poised between the mountain of purgatory and the city of Florence, displays the incipit Nel mezzo del cammin di nostra vita in a detail of Domenico di Michelino’s painting, Florence, 1465

Gems in the Age of Dante

For millennia, jewels and precious metals have been used as talismans and amulets, acquiring rich symbolic associations. Yet the capacity of lapidaries to actually cut precious stones is a relatively recent development—the first faceted gems arriving in Europe from India and the Far East following the fall of Constantinople in 1204.


At that time, Italy, which had played a critical role as a staging area for the Crusades and their associated commercial activity, was becoming a primary entrepôt for the importation of products from the East, many of which were previously unknown or that had been rare and costly to acquire—silks and calicoes, spices and exotic produce, ivory, gunpowder, improved methods for glassmaking and precious stones. With its skilled cadre of goldsmiths, Italy quickly rose to preeminence as a center for stone setting.

While polyhedral faceting had developed in the East and was used to shape rubies, sapphires, emeralds, and other comparatively “soft” stones, most gemstones continued to be cut in cabochon, that is, gradually brought into a round and regular shape through a tedious process of bruting and buffing.

Literary Gems

The Late Middle Ages saw a fluorescence of gemological literature, much of which elaborated upon the well-known works of classical antiquity such as Pliny’s late I century A.D. Naturalis historia (“Natural History”).  Dante would have been familiar with such lapidary treatises as Liber lapidum seu de gemmis, a poem in written in Latin hexameters by Marbodius of Rennes (ca. 1035–1123) – better known as Marbode – in which he describes some sixty stones and their magical properties. The work became renowned and was translated into French, Italian and many other languages and became the model upon which subsequent poetical works with lapidary themes were written by Dino Compagni, Bencivenni Zucchero and Francesco Sachetti. Many anonymous Italian lapidaries wrote in Latin, but one work, De mineralibus, was an important scientific treatise by the Dominican friar, Albertus Magnus (ca. 1206–1280), who is among the dozen intellectuals Dante “meets” in his fourth sphere of Paradise.

Many of Dante’s metaphors are based on the unique reflective and refractive properties intrinsic to all gems. We now know that his poetic “illuminated” imagery was based on his understanding of the physics of light.  He was most likely influenced by the ancient texts which were starting to emerge from monasteries and universities in the 1200s. Among them, particularly diffuse in Venice, were treatises on Euclidean and Pythagorean geometry which Italian gems cutters used to resolve complex problems such as the determination of angles, symmetry and the effect of light on a facet. In Paradiso, cut gemstones symbolize the revelation of the soul after the dross of the body has been chipped away – only then can the soul’s sparkling facets reflect divine light.


Here are just a few examples:


Truly do I entreat thee, living topaz!
Set in this precious jewel as a gem,
That thou wilt satisfy me with thy name.
(Paradiso, XV. 85-87)

In this canto, the souls are mounted, like gems in a cross of light. Here, Dante refers to his revered great-great-grandfather, the crusader Cacciaguida degli Elisei (ca. 1091-1148) as the “living topaz,” thus distinguishing him as a larger gem in this shimmering cross.  This term of endearment is the medieval equivalent of “a chip off the old block”. Also, by noting that his ancestor was a crusader, Dante was demonstrating he had elite ancestry.


Nor was the gem dissevered from its ribbon,
But down the radiant fillet ran along,
So that fire seemed it behind alabaster.
(Paradiso XV. 22-24)


The star sapphire, which exhibits a six-rayed star due to needle-like inclusions (often of the mineral rutile) within the gem, has been known since antiquity as the “Stone of Destiny,” its three crossed lines are thought to represent faith, hope, and destiny. As the stone is moved, or the light changes, a star appears, shines and moves due to a phenomenon called asterism. Here Dante shows the light following along the axes of the star of the gem creating a glowing cross.


From the glad nature whence it is derived,
The mingled virtue through the body shines,
Even as gladness through the living pupil.
From this proceeds whate’er from light to light
Appeareth different, not from dense and rare:
This is the formal principle that produces,
According to its goodness, dark and bright.
(Paradiso, II. 142-148)

In this passage, the largest and most lustrous of the pearls, the precious spirit of St. Benedict, comes forward to talk to Dante. As the father of monasticism in the Western Church, St. Benedict exemplifies the epitome of contemplative holiness—which stood in sharp contrast to the corruption of the Church Dante witnessed in his day. Because the pearl’s surface is round, it reflects light in a manner in which it appears to emanate from within. The soft radiance of a large, valuable, lustrous pearl is a fitting choice for such a mighty Christian leader.


It seemed to me a cloud encompassed us,
Luminous, dense, consolidate and bright
As adamant on which the sun is striking.
(Paradiso, II. 31-33)


When Dante enters the sphere of the moon and encounters Beatrice, he likens the experience to entering into a glistening diamond, a stone whose durability and perfection was unparalleled.


Dante uses rubies to describe Christian warriors and souls of the blessed.

The other joy, already known to me,
Became a thing transplendent in my sight,
As a fine ruby smitten by the sun.
(Paradiso, IX. 67-69)

This passage is particularly important as Dante chooses not to use the Italian word for ruby, rubino or rubinetto as he does later passages, but rather balasso, displaying his encyclopedic knowledge of gems, and his compulsion to expand the Italian language by creating a new word, a poetic Italianization of the Afghani word, balas, which referred to a rare and special type of ruby prized for its violet-rose hue. While called a ruby, it may have been a spinel that came from the ancient ruby and spinel mines of Badakhshan, Afghanistan, from which the shortened name, “balas” is derived.  The mines were famous since ancient times as they were also the source of the precious gem, lapis lazuli.

Returning from his trip to the East, Marco Polo (1254-1342) commented on the mines which in the future would provide monarchs with enormous red, sparkling gems called Balas Rubies.  It would only be in 1783 that a French mineralogist would classify spinel as a mineral separate from ruby, and thus render many crown jewels much less valuable, but nonetheless still stunningly beautiful.

Dante’s use of gems in Paradiso shows his knowledge of the subject was thorough. What is so moving, however, is his consummate display of literary genius in turning gems, beautiful in and of themselves, into literary gems—images and metaphors so powerful that they have been handed down through the ages to provide a feast for the mind and spirit.

Ann C. Pizzorusso is a geologist and Italian Renaissance scholar. After many years of doing virtually everything in the world of geology—drilling for oil, hunting for gems, cleaning up pollution in soil and groundwater, she turned her geologic skills toward Leonardo da Vinci and other Italian artists. Click here to view Ann’s website. Her latest book is The Gems of Dante’s Divine Comedy.

Top Image: Dante and Beatrice in Paradise. British Library MS Egerton 943  fol. 172r