Libra’s one old stone match rests on chrysolite, a word that has named more than one stone, so we set it aside and the sign is left with none. The modern list is opal, lapis lazuli, rose quartz, tourmaline, peridot and sapphire.
The word is chrysolite. For a very long stretch of its life it was a label for yellow-green and green gems in general, and writers reached for it and for topaz almost interchangeably, describing the same stones under either name with no way to tell them apart. GIA, writing about the green gem quarried on an island in the Red Sea, records exactly that history alongside the modern definition: peridot, also called chrysolite, is the gem variety of olivine, and ancient writers confused it with topaz because nobody could yet separate one yellow-green stone from another.
George Frederick Kunz, whose 1913 list is the ancestor of most modern accounts, gives Libra chrysolite. Peridot sits on the modern Libra list. Read at speed, that is an old source and a new one naming the same stone, and Libra joins the very short list of signs where anything survived. Read at the speed the word deserves, it is a question about what the word meant, and the answer is that it meant too many things to settle the point.
A word that has named more than one stone
This is the whole difficulty with reading old stone-lists, concentrated in one entry. A name in a fourteenth-century book is not a mineral. It is a word, and words for stones moved around a great deal before anyone could measure a refractive index or a hardness.
Kunz almost certainly meant gem olivine when he wrote chrysolite, because by 1913 the equivalence was settled. But almost certainly is a weaker thing than the match it is being asked to carry. When the modern Gemini list keeps agate, the old source and the new one are looking at the same banded rock and using the same word for it, and there is nothing to argue about. Chrysolite is not that. It is a word that spent centuries attached to whatever green or golden stone was to hand, and a match built on it is a match with a hole in the middle.
So Libra’s one apparent survivor is set aside, and the sign keeps none. That decision needs a rule behind it, because it would be easy to keep the ones that flatter a sign and drop the ones that do not.
None of this is an attack on the old writers, who were doing careful work with the tools of their day and had no instrument that could tell peridot from a yellow topaz on sight. It is only a reason to be slow. A stone-list four or seven hundred years old is a list of words, and a word is the least stable thing in mineralogy, changing hands between materials as fashions and languages shift while the rock underneath it stays exactly what it is.
What it takes to call two stones the same
The rule is simple and it is applied the same way every time. A stone counts as carried forward only where the old name and the modern name can be shown to point at the same material, not merely to sit near each other in the alphabet of gem words.
Against that rule, Libra’s chrysolite fails, because the word will not hold still. So does another case on the far side of the circle: a Spanish list of 1604 gives Capricorn chalcedony, and onyx sits on the modern Capricorn list, and onyx is banded chalcedony, so the two words may be pointing at one rock through two labels or at two different things. Both are printed, and both are declined on the same stated ground, that a name-deep resemblance is not evidence of a handed-down attribution. How many of the thirty-six cells survive once that rule is applied, and by which of two tests, is worked out on the Aquarius page. Libra is in neither count.
One thing does hold up, and it belongs to the planet rather than the sign. Agrippa’s 1533 table gives Libra beryl, and beryl is also the first stone in his chapter on Venus, the planet Ptolemy assigns to rule the sign. That is a real thread, though a short one, and it says more about how Agrippa built his table than about any tradition Libra can claim.
Opal, and the calendar behind the rest
Most of the modern six arrive by the calendar, and by nothing older.
Libra begins at the September equinox, which is an astronomical instant rather than a date, so the boundary slides by hours from one year to the next and the sign collects the tail of September and the bulk of October. The Aries page follows what that moving boundary does from the other side of the year. Jewelers of America gives September sapphire and October opal and tourmaline, and those three are on a Libra list because of where the sign falls, not because anyone assigned them to the scales.
Rose quartz comes in through Venus instead, which is at least a route with a reason, if a modern one. It is a stone a picture-matching habit would reach for on a sign about love and balance, and a good raw piece earns the reach. Vivid raw rose quartz is uncommon, since polishing usually does the work of bringing the colour up, and a specimen saturated enough to read across a room, the kind that turns up once in a tray of dozens, is a real outlier. GIA rates rose quartz generally stable in light and heat, which is not true of everything filed beside it.
Filed under names the shop never uses
Not one of the six can be looked up in a mineral reference the way a Libra shelf spells it.
Sapphire is corundum, aluminium oxide, Mohs 9, with no true cleavage. Rose quartz is quartz that happens to be pink. Lapis lazuli is not a mineral at all but a rock, an aggregate GIA describes as mainly lazurite with calcite and pyrite, and lazurite is the actual species in it. Tourmaline is a supergroup rather than a species, with schorl the black member and elbaite the coloured one. Peridot, the stone this whole page started with, is gem olivine, and olivine is a series with forsterite and fayalite at its ends.
Opal is the exception, and it is odd in the opposite direction from the rest. It is a valid species under its own name, hydrated silica, yet the Handbook of Mineralogy has no page for it, and it is the most fragile thing on the list by a wide margin. GIA puts it at 5 to 6.5 on the Mohs scale, calls its toughness very poor to fair, and warns that heat from strong light can open fracture lines called crazing. The stone the modern list leads with is the one that most needs looking after, and its own entry in the Crystalance Mineral Library sits under opal while the other five hide under corundum, quartz, lazurite, tourmaline and olivine. A reader working back from a Libra shelf to the minerals underneath it has to learn six different words to get there, and the one word the old lists seemed to share, chrysolite, turns out to be the least reliable of them.
Sources
- GIA, peridot from Egypt, on chrysolite, peridot and the old confusion with topaz: gia.edu
- George Frederick Kunz, The Curious Lore of Precious Stones, 1913, chs. IX and X: gutenberg.org
- Cornelius Agrippa, Three Books of Occult Philosophy, Book I ch. XXVIII on Venereal stones, 1651 translation of the 1533 original: esotericarchives.com
- Ptolemy, Tetrabiblos I.17, Robbins translation, on the houses of the planets: penelope.uchicago.edu
- Jewelers of America, birthstones by month: jewelers.org
- GIA, opal care and cleaning: gia.edu
- GIA, lapis lazuli: gia.edu
- GIA, rose quartz care and cleaning: gia.edu
