materialsTurquoiseفیروزه

said firuzeh in Persian; chalchihuitl in Nahuatl

also: firuzeh · pirozah · chalchihuitl · callais

materialIranAncient EgyptMesoamericaNorth AmericaThe Himalaya and TibetChinaMongolia and the steppeIran Egypt Mexico United States of America China Mongolia Greece

A hydrous phosphate of copper and aluminium, opaque, sky-blue where copper dominates and green where iron replaces it. It is soft for a gemstone — just under 6 on the Mohs scale, about the hardness of window glass — and porous, so it takes colour and oil from whatever touches it. It almost never forms crystals; it fills veins and fractures, or replaces a fossil.

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Old French turquois, 'Turkish', because the stone reached Europe through the Ottoman Empire from Khorasan in Iran
A misnomer, as the mineral is Persian and is not found in Turkey. Persian speakers called it pirozah, 'victory', which became Arabic fayruzah and modern Persian firuzeh. Pliny the Elder called it callais; the Aztecs called it chalchihuitl.
Folk etymology, labelled as one: The English name says the stone is Turkish. It is not; it only passed through. cited

When

c. 1500 BCE to now still carried cited

Period	Bronze Age to the present
How the date is known	excavated — dug up in a dated context
Note	Dated from turquoise beads and figures found in Greece from the Mycenaean era, 1500 BCE. Egyptian, Chinese and pre-Columbian North American use is also reported, with China given as a source for 3,000 years or more, but without a year this record can anchor to.

Years are stored astronomically — 1 CE is 1, 1 BCE is 0, 500 BCE is −499 — and printed the way a reader says them. How these dates are made.

What its carriers say it stops

Reported, attributed, not tested here. Each row below is somebody's claim, with their name on it.

Illness — sickness in general, where no cause is named citedsaid by the several ancient cultures whose common belief held that the stone changed colour with the wearer's health
Bad luck, unspecified citedsaid by Navajo use, described in the sources as spiritual protection and blessing
War citedsaid by Apache tradition, which holds that the stone affords the archer dead aim

The story

The claim made for turquoise almost everywhere it is worn is the same one, and it is unusual: the stone reports. Writers on the ancient cultures that used it — Egypt, the Aztecs, Persia, Mesopotamia, the Indus Valley, Shang China — record a common belief that turquoise held prophylactic qualities, that it changed colour with the wearer's health, and that it protected the wearer from untoward forces. A porous stone that darkens with skin oil and sunlight will in fact change, which is a rare case of a claim and a material property lining up.

In Iran it was the national stone for millennia, worked into everything from turbans to bridles, and used on domes because its blue stood for heaven on earth. Persian turquoise was often engraved with devotional words in Arabic script and the letters inlaid with gold. The Persian style went to India with the Mughals.

In Mesoamerica the Aztecs took turquoise as an embodiment of fire and gave it properties of heat and smokiness, inlaying it with gold, quartz, malachite, jet, jade, coral and shell into mosaic masks, some built on a human skull, and into knives and shields, bedded in resin, bitumen and wax. In the North American Southwest the Pueblo, Navajo and Apache prized it for amuletic use; Apache tradition holds that the stone gives an archer dead aim, and in Navajo use it is described as "a spiritual protection and blessing". Writers on the stone credit the Ancestral Puebloans of Chaco Canyon and the surrounding region with prospering greatly on producing and trading it.

Egypt mined it in Sinai and then imitated it: the blue-green glaze on faience exists in order to look like this stone and like lapis lazuli.

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Now

Tibetan and Mongolian silver and gold work still sets imported turquoise beside coral, with a greener hue preferred. Writers on the stone report both halves of the present trade without settling it: most pieces made today are roughly polished cabochons set simply in silver, meant for inexpensive export to Western markets, and are probably not accurate representations of the original style. The stone has also been devalued in finer grades by treatments, imitations and synthetics. Mining boomed and broke: prices peaked in 1890 and had collapsed by 1912, ending large-scale operations.

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