How to Tell If Turquoise Is Real

Real turquoise is a copper aluminum phosphate — 4 to 6.5 on the Mohs scale. Three checks matter: matrix that runs through the stone rather than sitting on its surface, a price that fits the grade, and a seller who names the mine and the treatment. Most home tests are folklore.

What real turquoise actually is

Turquoise is a hydrated copper aluminum phosphate — CuAl₆(PO₄)₄(OH)₈·4H₂O. It is a secondary mineral, which is the part most people miss. It doesn't crystallise into a bed of its own. It gets carried in solution and deposited into pockets and crevices that were already there, in faulted and fractured zones of weathered rock at the water table's edge. That is why turquoise comes out as nuggets and veins rather than crystals: the stone takes the shape of the crack it filled.

It is a desert gem in the literal sense. Deposits sit between roughly 3,000 and 8,500 feet, on low, unremarkable hillsides in dry country, most often within, near, or above copper and gold deposits. A miner reads the ground for iron-stained limonite, chalcedony, and quartz at the outcrop.

The matrix is the host rock. The brown, black, or golden webbing in a stone is the rock the turquoise grew in, and its pattern is a record of how the pocket was shaped: the more the host rock was broken up and the more evenly the turquoise solution spread through it, the more likely you get the fine spiderweb that collectors chase. Matrix is not damage. It is the stone's address.

Hardness runs 4 to 6.5 on the Mohs scale. Lowry gives 4 to 6.5 for usable natural turquoise, and 4.5 to 6.5 for the polish-grade fraction specifically — worth knowing both numbers, because you'll see each quoted. And here is the figure that explains the entire turquoise market: only about 15 percent of the world's turquoise production comes out of the ground hard enough to grind, shape, and take a polish. The other 85 percent is soft, pale material the trade calls chalk — some of it soft enough to write on a chalkboard. Hold onto that number. Everything in the next section follows from it.

Colour is a question of where the stone was dug. Compare blue against blue and green against green; several famous mines produce green and are collected hard on their own terms. Be sceptical of tidy chemistry stories about what makes a stone green — turquoise sits in a group of near-identical minerals that differ by a single element, and these get identified incorrectly even in a lab. The honest answer is that colour is a function of the deposit. To understand why the mine a stone came from matters so much, start there.

Real, stabilized, dyed, imitation: the honest taxonomy

Eighty-five percent of what comes out of a turquoise mine is too soft to cut. That single fact is why this vocabulary exists, and why anyone who tells you stabilized turquoise is a scam is selling you something.

Natural. Cut, shaped, and polished with nothing added. The hard 15 percent — the material hard enough to take a polish without falling apart or burning on the wheel.

Stabilized — the same thing as treated; the two words describe one process. Soft, porous stone is soaked and cured in liquid plastic, usually a polyester resin. The resin hardens in the pores, and the stone comes out tougher and more compact. It also comes out darker, for a reason worth understanding: the resin makes the stone less porous and more translucent, the way a wet patch on cloth reads darker than the dry cloth around it. If the turquoise is blue, it gets bluer; green, it gets greener. No dye is added. The bond is permanent, and the stone then resists oils and detergents — which is why stabilized turquoise is often the more practical stone to wear daily. This is not a lesser stone dressed up. It is real turquoise, made wearable. Say so.

Oiled or waxed. Softer material finished in oil- or wax-based polish. It looks good on the shelf and it does not hold: these stones lose or shift colour as the oils break down in sunlight and changing temperature, and they readily absorb whatever else they touch. A dull, waxy surface is one of the few visual flags that genuinely means something.

Dyed. Colour added. The distinguishing failure is that dye is not stable — the colour breaks down over time with direct sunlight or changing temperatures. Stabilization is permanent; dye fades. That is the line between the two.

Imitation — not turquoise at all:

• Howlite and magnesite. Naturally white minerals, dyed to imitate turquoise. The most common fake you will meet.
• Block / reconstituted. Mineral compositions pressed or moulded together with a plastic binder, with rock, sand, pyrite and colour added to imitate matrix. The tell: soft enough to be scratched easily with a knife blade.
• Plastic and glass. Plastic coloured with blue pigment; glass cabochons going back centuries. The Southwest's most famous glass imitations are the Hubbell beads, traded through the Hubbell Trading Post near Ganado, Arizona — glass made to pass as turquoise.
• Gilson. A lab synthetic developed by Pierre Gilson in the 1970s, made to the clarity and robin's-egg blue of Persian turquoise, later with a black matrix added. Sold worldwide.

The one that matters most: a fake can wear a matrix. Pyrite and dye get added to plastic specifically to counterfeit that webbing, and processed chalk can be given matrix in the treating. Matrix is a real clue and it is not proof.

How to actually tell, and which tests are folklore

Start here, because it saves everyone time: there is no reliable home test. No single patch test identifies the condition of every turquoise on the market, and visual expertise is only as good as the source of the knowledge behind it.

The checks that hold up:

1. Ask what mine it came from, and what was done to the stone. This is the strongest check available to a buyer, and it costs nothing. A seller who knows their material can answer both. One who deflects has told you something.
2. Get it in writing. Reputable dealers guarantee a purchase in writing. A verbal "it's natural" is not a disclosure.
3. Read the surface, not the shine. A high polish proves nothing — polish depends on the lapidary's wheel, not the stone's honesty. But a dull, waxy surface is a genuine flag that a stone may have been oiled or waxed rather than cut hard.
4. Read the matrix knowing its limits (see above). Pattern that sits on a stone rather than running through it is the thing to catch.
5. Sanity-check the price against the claim — see the next section.
6. Pick it up, and look at the back. Our practice at the counter, not a lab test: real stone and solid silver carry weight, and a set stone sits in a bezel while a glued one hides its edges.

The tests you've read about that don't work:

If a page recommends a test that damages a stone you already own, it isn't advice. When you're ready to verify who made a piece, the hallmark on the back is where you start.

What real turquoise should cost

No honest page can give you a price per carat, because turquoise isn't priced like diamonds. There is no universal grading lab. Price is set by five things: condition, source, colour, clarity, and matrix.

• Source does heavy lifting. A named mine functions the way a certificate does elsewhere, and the famous mines each carry their own grading system — a high-grade Bisbee is judged on different terms than a high-grade Number Eight. Which is precisely why the name is worth stealing. Mexican turquoise has been misrepresented and sold as Kingman since before the 1970s, and Mexican and Chinese stone has moved by the ton under the names Morenci, Sleeping Beauty, Lander Blue, and Lone Mountain. Treat a mine name as a claim, not a credential: a buyer who wants stone from a classic mine needs a written guarantee of the source, from the miner and the seller both.
• Darker is rarer. The deepest colours are the hardest to find, so they carry the most value — but compare within a colour, blue to blue and green to green.
• Treated material is cheap to produce, and should be priced that way. It comes from the soft fraction that would otherwise be unusable — possibly 80 percent of all turquoise mined — and the process is not expensive. Treated turquoise should not command prices anywhere near untreated stone. Not because it's shameful. Because it's abundant.

The trap runs in both directions. A price far under the market is a flag. But the more dangerous case is the opposite: when the intent is to deceive, the imitation is priced close to the natural gemstone — because a realistic price is what makes the lie work. Add the perennial tourist-trade tell: the shop in a continuous going-out-of-business sale. The reliable signal is not the number. It is whether the number comes with a source.

How T.Skies discloses every stone

We tell you what the stone is, where it came from, and what was done to it. Not as a courtesy — as the baseline the law already sets and most of this trade ignores. The FTC Jewelry Guides (16 CFR Part 23) are specific: under §23.24, a seller must disclose that a gemstone has been treated when the treatment isn't permanent, when it creates special care requirements, or when it significantly affects the stone's value. Stabilized turquoise routinely meets that last condition; oiled or waxed stone meets all three. §23.1 makes misrepresenting a product's treatment, origin, or value deceptive on its face. And §23.27 bars the words real, genuine, and natural for anything produced artificially — words this trade throws around freely.

What that looks like on our listings:

• The stone. Natural, stabilized, or otherwise — stated, not implied.
• The source. Our turquoise comes principally from named mines such as Kingman, the Mineral Park ground in Mohave County, Arizona; Royston, in Esmeralda County, Nevada, where the name covers several neighbouring deposits worked as one district; and Campitos, in Mexico. We name that last one as Mexican turquoise because the lie in this trade runs the other direction. Our primary stone supplier is Toltec Turquoise. Ask which mine a particular stone came from — that's a question we can answer.
• The maker. Every gallery piece is stamped with the maker's name or hallmark, and listed with the artist's name and tribal affiliation, with their permission. On collaboration pieces bearing both an artist's hallmark and the TSKIES hallmark, the listing says so.

None of this requires trusting us. It requires knowing what to ask. The hallmark on the back is in our hallmark guide, and the maker has an entry in our directory of 680 silversmiths.

Frequently asked questions

Sources

• Joe Dan Lowry & Joe P. Lowry, Turquoise: The World Story of a Fascinating Gemstone — formation, hardness, treatments, testing, grading.
• Oscar T. Branson, Turquoise: The Gem of the Centuries — stabilization process and economics.
• U.S. Federal Trade Commission, Guides for the Jewelry, Precious Metals, and Pewter Industries, 16 CFR Part 23 (§§23.1, 23.24, 23.27).
• Gemological Institute of America — gia.edu.

Related entries

• The T.Skies Silversmith Directory — named artists, nations, hallmarks
• How to read a hallmark & authenticate the maker
• Southwest Jewelry Guide (hub)
• Shop authenticated turquoise jewelry