Emerald is May’s birthstone. The property classical writers name for it, across the better part of four centuries, is not love and it is not renewal. It is eyesight.
Theophrastus, writing in Athens around 315 BCE, gets through the green stone in a few lines and one of them is this: “It is also good for the eyes, and for this reason people carry seals made of it, so as to see better.” Not worn for protection. Carried, as a seal, by people who wanted to see.
The rest of his account is as short and as practical as that line. It has a power, he writes, of making “the color of water just like its own”, and the effect scales with the stone: a middling one colours a little water, the largest kind colours all of it. He knows where it comes from, the copper mines of Cyprus and an island off Chalcedon, and he knows it is rare and usually small, though he passes on reports of enormous ones, including a stone said to have been sent to Egypt six feet long. None of that is symbolism. It is a description of a material, its sources, its size range and what it is good for.
Pliny is still saying it three and a half centuries later, at greater length and with a trade attached. Somewhere in between, nobody wrote down a reason.
That claim survived from one end of the classical world to the other, and it is the one thing about the stone that a May reader today will not be told.
Pliny on the green, and on tired eyes
Three and a half centuries later, Pliny gives the emerald third rank among gems and then spends most of a chapter saying why. In the Victorian translation by Bostock and Riley, Natural History 37.16 runs:
“Indeed there is no stone, the colour of which is more delightful to the eye; for whereas the sight fixes itself with avidity upon the green grass and the foliage of the trees, we have all the more pleasure in looking upon the smaragdus, there being no green in existence of a more intense colour than this. And then, besides, of all the precious stones, this is the only one that feeds the sight without satiating it.”
Then comes the line that carries the working detail: “Even when the vision has been fatigued with intently viewing other objects, it is refreshed by being turned upon this stone; and lapidaries know of nothing that is more gratefully soothing to the eyes, its soft green tints being wonderfully adapted for assuaging lassitude, when felt in those organs.”
Lapidaries know of nothing better. That is a claim sourced to a trade, by a man who talked to tradespeople, about the working conditions of their eyes. Theophrastus had described people carrying the stone in order to see better; Pliny describes people who cut stone all day putting the work down and looking at one. Three and a half centuries apart, and the two are not quite the same claim. One is an aid, the other is relief. Both are about a working eye rather than about a virtue.
Pliny keeps to that practical register. The stones “appear all the larger to the sight” when viewed from a distance, he writes, “reflecting as they do, their green hues upon the circumambient air”, which is an observation about how a colour behaves at the edges of an object and not about a power the object has.
The claim also sits in an unusual place. Most of what gets said about a gemstone is a statement about the stone, that it protects or attracts or draws something off. This one is a statement about the person looking. Whatever happens, happens in the eyes of the observer, and the stone’s only job is to be a particular green and hold still. A claim shaped that way can be tested by anyone with tired eyes and something green to hand, which may be why it lasted as long as it did without ever needing a story to carry it.
The chapter ends with a detail that has been distorted since. Pliny notes that a flat-surfaced smaragdus “reflects the image of objects in the same manner as a mirror”, and then: “The Emperor Nero used to view the combats of the gladiators upon a smaragdus.” Upon, or in. Not through. Bostock and Riley take up the suggestion that Nero was short-sighted and using a lens, and reject it in their own note: “The passage, however, will hardly support such a construction.” The Loeb translators render it as a reflecting stone. Nero was most likely watching a reflection, in a chapter about what green does for the eyes.
The reach of one word
The smaragdus is not simply emerald, and that qualifies every ancient reference here. Pliny lists twelve kinds in chapter 17, sorted by where they come from and how they behave in light, which is a dealer’s classification rather than a mineralogist’s. The Scythian ranks first, the Bactrian second, the Egyptian third, and the rest, he says, come out of copper mines. In the next chapter he reports Democritus adding others, among them a “Persian” stone that is “destitute of transparency” and resembles the eyes of cats and of panthers. Bostock and Riley put the conclusion in their own note: “The Emerald, and various other green precious stones, were included under this name.”
The same editors pass on Beckmann’s argument about Nero, which runs on size. On his account real emeralds are too small to serve as mirrors, so the ancients must have been classing fluorspar, green jasper and green glass among their emeralds. The note also records Ajasson’s alternative, a dioptase or a green corundum. Whatever Nero had, the category was wide enough to hold several minerals.
None of which weakens the eye claim. If anything it sharpens it, because what is being praised across the kinds Pliny ranks highest is the one quality they have in common. Theophrastus and Pliny are describing a colour rather than a mineral species, and recommending it to anyone whose eyes hurt.
The two records, side by side
The classical account gives a use. On that account this green rests the eyes more than any other, and people who work close should keep some near. No origin story comes with it, no god, no season, and nothing about the heart.
Crystal practice reads emerald quite differently. It places the stone at the heart, the energy centre associated with love and emotion, and speaks of growth and of steady affection. That is what the tradition holds, and it is a coherent reading of a green stone in a spring month.
What is not in the tradition, anywhere, is the eyes. The property two classical authorities record three and a half centuries apart, one of them sourcing it to the people who handled the material daily, is the one that did not make the journey, and the point at which it fell away is not recorded either.
The mineral explains none of this. Emerald is beryl coloured green by chromium, vanadium, or both, and it reaches the counter with internal fissures that the trade tolerates in it and would reject in almost any other gem. That is a fact about buying rather than about believing.
May sits at the end of a very long stretch of admiration for one colour, and the reasons given for admiring it have been exchanged at least once along the way. The later set is the one in circulation, and what crystal is for Taurus gives the sign-by-sign reading of it. Through all of it the emerald has gone on being beryl, which the Crystalance Mineral Library sets out without reference to any month at all.
The earlier set is still on the page, in Theophrastus and in Book 37, and as advice it has aged better than most ancient writing about stones. Look up from the work. Look at something green.
Sources
- Theophrastus, On Stones, sections 23 to 25, translated by Caley and Richards, for the eye claim and the carried seals: topostext.org
- Pliny, Natural History 37.16, Bostock and Riley, for the green and the eyes, the mirror, Nero, and the editors’ notes on the lens reading and on Beckmann: perseus.tufts.edu
- Pliny, Natural History 37.17, for the twelve kinds of smaragdus: perseus.tufts.edu
- Pliny, Natural History 37.18, for Democritus and the Persian stone: perseus.tufts.edu
- Pliny, Natural History, Book 37, Rackham, Jones and Eichholz translation, rendering the Nero passage as a reflecting stone: wikisource.org
- Handbook of Mineralogy, beryl, for the composition: handbookofmineralogy.org
