How to tell a natural stone from a fake at the window and in your hand

Take the piece, walk to the window and turn the stone toward the light. Those five seconds settle half the questions about authenticity, because a natural mineral is almost never spotlessly clean inside, while a resin casting is uniform all the way through. Weight, temperature and comparing the beads on one strand with each other cover the rest. No instruments needed. All it takes is the habit of holding your eye on a stone for longer than a second.

Four checks that need nothing at all

None of them calls for a loupe, a reagent or the seller's permission.

1. Toss the bead in your palm and compare what you feel with what your eye promised. Quartz has a density of 2.65 g/cm³, acrylic around 1.2, so a quartz bead is twice as heavy as a plastic one, and the hand catches that difference far better than any density table.
2. Hold the stone against the inside of your wrist and count to five, the skin is thinner there and the difference reads more clearly. A natural stone draws the heat away and stays cool, plastic warms up under your fingers. With glass the trick is useless. It feels as cold as quartz and gives up that chill in the palm just as slowly.
3. Hold the bead up to the window and look through it at an angle, turning first one side to the light, then the other. A natural stone almost always has something extra inside: haze, hair-thin needles, small clouds, healed fractures with a rainbow sheen. Resin poured into a mould sets as one even mass, and it has nothing to show inside.
4. Look at the price, but remember that it works in one direction only. A large transparent stone in a rare shade for three hundred rubles will almost certainly turn out to be some other material. The reverse does not hold: dyed glass turns up in expensive pieces too.

The fifth check stands apart, because it is not about one stone but about the whole strand at once. In a natural bracelet the shade and the pattern wander: one bead is lighter than its neighbour, another is cloudier, a third has a crack right by the hole. A set where all twenty look like carbon copies means either pressed chips or glass. Makers of cheap imitation rarely bother with variation, because an even product photographs richer and sells faster.

Tests that ruin the piece

Half of the home methods in the search results are instructions for wrecking your own jewellery.

Do not test hardness with a needle or a knife. The hardness test was invented for a rough specimen out of a mineralogist's box, on a polished cabochon it leaves a groove instead of an answer, and that scratch will never grow back.

Do not hold the piece to a flame. A sharp change in temperature splits a stone along its internal stresses even where the hardness is seven, glued doublets come apart at the seam, and the cord and the glue inside a bead burn away before any result appears. Plastic gives itself away by weight without a lighter.

Do not drip vinegar on a stone. A positive result in this test means a ruined piece, so it is hard to call it a test at all.

Do not send the piece into an ultrasonic bath. The bath tests nothing, but it cleans rather harshly, and stones with cracks or a wax impregnation sometimes do not survive it. We drew the line between cleaning and damage in the care rules.

There is a difference between a fake and a treatment, and the two should not be confused: tinted quartz is still a natural stone that was worked on before it reached the setting. A fake is when there is no natural material at all. The first calls for a plain line in the description, the second means you should not be buying here.

All of this is easier to practise on pieces you know, so we will name our own right away, with prices, and then talk only about stones. Rose quartz is strung into the substantial bracelet KHALISI sunrise at 25,900 ₽ and into the stainless steel bracelet Viviana at 6,500 ₽. Moonstone, quartz and labradorite stand together in the ring Spheres at 5,500 ₽, and labradorite alone is strung into the necklace Dragon Wing at 39,000 ₽. Rock crystal went into the earrings Night dew at 5,900 ₽ together with rose quartz and moonstone. All five are made by hand and exist as a single piece each, so a second stone with the same pattern is nowhere to be found.

Moonstone and labradorite: imitation cannot move

In both stones the main thing happens when you turn them, and that is the very place where copies break down. The light in them should travel, gather into a band and go out, while in glass it lies still.

Moonstone

What gets faked here is the glow, and it gets faked with glass. Opalite, a frosted glass with a milky cast, glows evenly and the same from every side, and against the light it goes a warm orange tone that feldspar never has. Opalite is cheap, and that is its only virtue. In real adularia the bluish sheen lives just under the surface: tilt the stone toward a lamp, turn it slowly, and the light will gather into a band, ride along with your hand and go out. Opalite often shows neat round bubbles, while the body of a natural stone between flashes stays milky and half-transparent, often with fine internal cracks. Why that sheen appears and where the stone got its name we explained in the piece on moonstone.

Labradorite

The flashes of labradorite are born at the boundaries of the finest lamellae the mineral split into as it cooled, so they light up only within a narrow range of angles. Turn it a couple of degrees and you are holding a dull dark grey stone. Glitter glass sparkles always and from every side, and its sparks are pinpoint and scattered, as if semolina had been spilled over a dark ground, whereas in labradorite the flash comes as a solid field and floods half the bead at once. A confusion of its own lives in the name: “rainbow moonstone” on a shop shelf is most often pale labradorite, and even honest sellers label it that way. About the mineral itself we wrote in more detail.

Rose quartz and rock crystal: imitation is too even

A different rule works here, because what you look for are the irregularities nature allows and a casting mould cannot repeat. The copy is almost always tidier than the original.

Rose quartz

The pink shade comes to quartz from microscopic fibrous inclusions, and so the stone is almost always a little cloudy and unevenly coloured: in one bead the tone is denser, in the next it is barely there. What should put you on guard is an even strawberry colour at full transparency, because that is what dyed glass looks like, not quartz. Fully transparent rose quartz does exist in nature, but it is rare, expensive and almost never ends up in inexpensive bracelets with large beads. In dyed milky quartz the colour collects in the cracks and around the drill hole, so those are exactly the places to examine, while the overall tone deceives easily. Where the colour itself comes from and why such a bracelet should not sunbathe on a windowsill we went into separately.

Rock crystal

Transparent quartz is rarely spotlessly clean, and inside it you can see the ghostly outlines of earlier crystal faces, hair-thin needles and healed fractures that catch the light in rainbows. Glass has none of that, but it does have round bubbles and striae, swirling bands in the body of the material, visible against the light at an angle. Striae give glass away more surely than bubbles, because a bubble can go unnoticed, while a swirling band runs across the whole bead and shows on the very first turn. There is a difference in weight between quartz and glass, but a small one, 2.65 against roughly 2.5, so here the eye is more reliable than the palm.

How a seller with nothing to hide behaves

There is usually no certificate for beads and cabochons, and that is normal, because a gemmological report costs more than the stone and is ordered for large gems in expensive settings, not for a strand of beads. The paper on its own decides nothing, but there are things a seller shows at the first question.

• A macro photo of your exact piece in daylight, not a catalogue image from someone else's warehouse.
• A video where the stone is turned under a lamp so you can see how the glow behaves.
• The exact name of the mineral with no marketing substitutions, because opalite is called opalite and pale labradorite is called labradorite.
• The treatment, if there was one, whether tinting, wax impregnation or gluing.

Judging us by the same list is fair, and one hole we will name ourselves. There are two metals in the workshop, stainless steel and brass, but the material is not filled in on every product page, and while that is so, the question “what is it made of” stays a legitimate one, and we answer it in messages. We are fixing this, but it is not fixed yet. The same goes for stone treatment and for returns: fourteen days to change your mind is the buyer's right, not a favour from the shop.

A seller with nothing to hide behaves rather boringly. They do not rush your decision, do not push you with a discount that ends this evening, call the stone by its real name and calmly admit when they do not know something. To a direct question about origin they answer directly, and if what comes back instead is offence, the trouble almost never lies in your suspicion.

What people ask

Can you test a stone at home with no loupe and no instruments?

You can, and four moves are enough in most cases: toss the bead in your palm, hold it against the inside of your wrist, look through it at the window and compare the beads on the strand with each other. The hand catches the difference in density by itself: 2.65 g/cm³ for quartz against roughly 1.2 for acrylic gives double the weight at the same size. A needle, a lighter and vinegar, on the other hand, test nothing at all, they only leave a scratch, a crack or a dull spot that can no longer be removed.

The seller writes “moonstone”. How do I know it isn't opalite?

Tilt the stone toward a lamp and turn it slowly. In real adularia the bluish sheen gathers into a band, rides along with your hand and goes out, while opalite glows evenly from every side and goes a warm orange tone against the light. Round bubbles inside also give glass away. Check the name itself separately: “rainbow moonstone” on a shop shelf most often labels pale labradorite. Our moonstone sits in the ring Spheres at 5,500 ₽ next to quartz and labradorite, so all three are visible in one turn of the hand.

All the beads in the bracelet look identical. Is that a bad sign?

Most often yes. Nature does not hand out twenty identical beads in a row: one has a denser tone, another is cloudier, a third has a crack by the hole. Perfect evenness across a set means pressed chips, dyed glass or plastic. While you are at it, look at the edges of the drill holes, because in dyed beads the colour collects exactly there, and the overall tone deceives easily. Our bracelets are strung by hand and exist as a single piece each, so variation between beads is the norm in them, not a defect.

The stone feels cool in my palm. So it can't be glass?

It can. Glass feels as cold as quartz and gives up the chill just as slowly, and the difference in density is too small to catch by hand: 2.65 against roughly 2.5. Here it is the look against the light that decides. Swirling bands in the body of the material (striae) and round bubbles mean glass, and striae are more reliable than a bubble: a bubble can go unnoticed, while a band runs across the whole bead and shows on the very first tilt. Natural quartz shows something else: ghostly outlines of earlier crystal faces, hair-thin needles, healed fractures with a rainbow sheen. Our rock crystal is in the earrings Night dew at 5,900 ₽.