Buying a crystal should be a pleasure. You find a beautiful point, sphere or cluster, imagine where it will sit on your shelf, and start picturing it in your collection.
Then you notice the colour or the clarity looks a little too perfect, and a question arrives: what exactly am I buying?
It is a fair question. Glass can look like quartz, dyed howlite can pass for turquoise, and a cluster assembled by hand can look very like one that grew underground. None of that is obvious from a photograph.
The good news is you can learn a surprising amount with a few checks at home. No laboratory, no specialist kit. Your eyes, a bit of background, and the habit of reading the label properly.
One thing runs through all of this: natural, treated, crafted and man-made are different categories, not a ranking from good to bad. A glass scrying ball is an excellent scrying ball. Treated quartz has a finish natural quartz simply does not. A crafted cluster makes a striking display piece.
The point is knowing which one you are buying.
Test 1: glass or quartz? Try the cheek test
Clear spheres are the place to start, because polished glass and polished quartz look remarkably alike. Both are transparent, glossy and clear, and a photograph settles nothing.
Pick the sphere up and hold it against your cheek.
Quartz feels cold because it conducts heat away from your skin several times faster than ordinary glass does. Your skin loses heat quicker, and you read that as cold. That is the whole mechanism, and it is why the test works at all.
If the sphere feels properly cold and stays that way for a few seconds, quartz is a real possibility. If it warms to neutral almost immediately, you are probably holding glass.
Room temperature and thickness both affect the sensation, so compare two objects of similar size rather than trusting one touch in isolation.
Next, put it under a bright light and look for tiny round bubbles. Bubbles form when glass is made. Natural quartz has inclusions and fractures, but neat spherical gas bubbles point firmly at glass.
Then turn it slowly and look for a seam. Moulded glass often carries a faint line where the two halves of the mould met. A continuous line running around the sphere is a strong sign. Not every glass object has one, so its absence proves nothing either way.
There is also an optical difference worth knowing. Quartz is birefringent: it splits light into two rays travelling at different speeds, because its optical behaviour depends on direction through the crystal. Glass has no crystal structure at all, so it cannot do this.
Don't scratch a finished sphere to find out. Quartz is harder than ordinary glass, so the test works, but you will damage a polished surface to learn something the listing should already tell you.
Ours do. Our crystal balls are labelled "K9 optical glass" and "Not stone". K9 is an optical glass used for clear polished objects, and a scrying ball wants exactly that flawless clarity. Quartz that clear at the same size would cost a fortune.
Test 2: dyed stone? Follow the colour into the cracks
Colour is half the pleasure of collecting stones. Natural minerals come in an extraordinary range, and dyed stones bring vivid colour to slices, polished pieces and jewellery.
To work out which you have, look closely under a bright light, and pay attention to the cracks, pores and edges rather than the flat polished faces.
Dye collects in tiny fractures and pits. In those places the colour looks darker and more intense than it does on the surrounding surface. On a dyed stone you often see bright colour tracing a network of cracks like ink running through paper.
Howlite sold as turquoise is the classic case. Natural howlite is white or pale grey with distinctive grey veining. Dye it blue and those veins stay visible underneath.
Look at the pattern, because this is the giveaway. Howlite's grey lines branch across the stone like a road map. Turquoise's natural matrix is irregular and patchy, nothing like as orderly. The blue does not erase the howlite structure, it just sits on top of it.
Bright agate slices are the other common one. Agate takes dye readily, and the colour gathers in fractures or forms unnaturally intense bands. An electric blue or hot pink slice is worth a close look at the edges.
Dyeing techniques vary and some are very even, so no visible pooling does not prove the colour is natural. Check the listing for "dyed", "colour enhanced" or "treated".
And keep the distinction straight: dyed howlite is still howlite. The treatment changes the appearance, not the identity of the material underneath.
Test 3: selenite? Your fingernail settles it
Selenite has a silky lustre and a soft, luminous look that nothing else quite matches. It is popular as towers, spheres, hearts, palm stones and engraved plates. It is also much softer than almost anyone expects.
Selenite is a variety of gypsum with a Mohs hardness of 2. A fingernail sits around 2.5, and a copper coin is harder still. Your fingernail will scratch it.
Pick an inconspicuous spot on the underside, press gently and draw your nail a short distance. If it takes a mark, that is consistent with selenite. You do not need to press hard, and you are not trying to carve your initials into it.
Other soft materials scratch too, so the result confirms softness rather than identifying every white stone on earth. But combined with the silky fibrous look, it is close to conclusive.
That hardness has a practical consequence most people learn the hard way. Selenite should never share a drawer or a pouch with harder stones. Quartz at Mohs 7 will scratch it during perfectly ordinary handling. Store it on its own, somewhere soft.
The other rule: never wash selenite. Gypsum is water-soluble, so water dissolves the surface and kills the finish. No rinsing, no soaking, no wet cloth, and no leaving it out in the rain for a full moon.
Use a soft dry cloth or a dry brush, and go carefully around engraved detail.
None of this is a defect. Softness and water sensitivity are simply what gypsum is, and a listing should tell you so.
Test 4: precious metal? Check the hallmark
With silver or gold, colour and weight tell you nothing about purity. A silver-coloured chain might be plated base metal. A gold-coloured ring might be solid gold, gold plated, or an alloy of something else entirely.
In the UK, hallmarking law gives you a reliable answer. A hallmark records that the metal has been independently tested and meets the stated standard.
Look in the discreet places: inside a ring, near a clasp, on the underside of a pendant. The marks are small, so use a magnifier and good light.
A full UK hallmark has three parts: the sponsor's or maker's mark, the fineness mark, and the assay office mark. The fineness number gives the proportion of precious metal.
925 is sterling silver. 375 is 9-carat gold, 585 is 14-carat, 750 is 18-carat. Platinum and palladium have their own standards.
Weight matters, because UK law sets thresholds below which hallmarking is not compulsory:
- Gold: 1 gram
- Silver: 7.78 grams
- Platinum: 0.5 grams
- Palladium: 1 gram
Those figures are the weight of the whole article, not the pure metal in it. An item under the threshold can be sold legally without a hallmark, so a missing mark on something very light does not mean it is fake.
Read the wording too. "Gold plated" is a layer of gold over something else. "Gold tone" is a colour and a promise of nothing. "Silver plated" is not sterling silver, which is an alloy of 92.5 per cent silver.
A number stamped on an item is not by itself a UK hallmark. If the marks are unclear and the piece was expensive, a reputable jeweller will read them for you.
Test 5: read the adjective
This is the most useful test of the five, and you can do it before you even reach for your card.
Read the title and the description, and pay attention to the adjectives. "Crafted", "reconstituted", "created", "enhanced", "aura" and "man-made" all describe how a material was formed, changed or assembled.
They are not warnings. They are information. Here is what each one actually means.
Crafted
Made or assembled by people. In the crystal trade a crafted cluster is built from separate natural points arranged into a finished cluster.
The points are genuine quartz. The arrangement did not grow that way underground. If you specifically want a natural formation, that matters. If you want a striking display piece with an even spread and a base that sits flat, a crafted cluster is the better object.
Reconstituted
Made by combining fragments, particles or powder into a new solid form, usually with a binder. It can contain genuine mineral material, but it is not one intact natural crystal.
Created
Produced through a controlled process rather than formed in the ground. In the gem trade it usually means laboratory-grown, which has the same chemical composition and crystal structure as the natural stone.
A laboratory-grown gemstone, a glass imitation and a composite made from fragments are three different things. Check the specific wording.
Enhanced
Treated to change colour, clarity or appearance. The word alone does not say which treatment. Heat, dye and surface coatings are very different processes, and a good listing names the one used.
Aura
The iridescent, rainbow-like finish you see on aura quartz. It starts as quartz and receives an extremely thin metallic coating, usually applied by vapour deposition.
Because the colour sits on the surface rather than running through the stone, it can wear at edges and raised points where it gets handled most. That is the nature of the finish, not evidence the quartz underneath was ever fake.
Ours say "quartz treated to carry an iridescent sheen across the points", which tells you both halves of the story.
Man-made
Manufactured rather than formed naturally. It covers glass, resin and synthetic gemstones, and it says nothing about quality. Optical glass is made precisely for its clarity and consistency.
These terms overlap. A crafted object can contain natural quartz, an enhanced stone can have a natural base, and a man-made piece can be beautifully finished. The question is always the same: what is the material, and what happened to it before it reached you?
What the tests cannot tell you
These checks give you clues. They do not establish everything about a stone's identity or history.
Origin is the obvious gap. Two pieces of the same mineral can look quite different depending on the conditions they formed in, and stones from opposite sides of the world can look nearly identical. No home test tells you which mine a specimen came from.
Grade is the other. "High grade" and "gem quality" are not standardised terms. Clarity, colour, inclusions, damage and finish all feed into how a piece is judged, and a polished sphere and a rough chunk of the same mineral simply show you different things.
Use stated dimensions and weights rather than photographs to judge size. For bags of rough crystals, check the weight and the approximate piece count.
How to read a listing before you buy
A good listing answers the obvious questions without making you decode anything.
Check the material first. Does it say quartz, amethyst, selenite or glass? "Crystal" on its own is not a material.
Then look for treatment and construction. Is the colour natural or enhanced? Is the cluster grown or assembled? Is the sphere stone or glass?
Then dimensions, weight and photographs, so you know the real size and whether you are seeing the actual item.
Then care instructions. Selenite needs dry handling. An aura coating needs care at the edges.
And finally, check the price makes sense against the description. A large, exceptionally clear quartz sphere and a K9 optical glass sphere are very different products with very different material costs, and the listing should make that plain.
What we do about it
We think a listing should tell you what you are buying in plain English, so we name the material and describe the treatment or construction wherever it matters.
Our crystal balls say "K9 optical glass" and "Not stone". A scrying ball wants the clarity and the smooth surface optical glass gives, and we would rather say so than let you assume it is quartz.
Our aura pieces say "quartz treated to carry an iridescent sheen across the points".
Our crafted clusters say "sold as a crafted cluster, built up from natural points rather than lifted out of the ground in one lump".
We also stock plenty of natural quartz and amethyst in rough, polished and naturally formed pieces, so you can compare them directly against the treated and crafted ones and pick the thing you actually want.
Crystal balls run from £5.00 at 5cm to £178.99 at 20cm. Selenite towers start at £5.00. Medium aura quartz is £17.49, and the crafted clusters are £45.00 and £48.00. Free UK delivery over £40.
Your questions, answered
Can I identify a crystal just by looking at it?
You can spot useful clues: bubbles in glass, dye pooled in cracks, the softness of selenite. Combine what you see with what the description says and you will be right far more often than not.
Does treated mean fake?
No. A treated stone usually has a genuine mineral base with an altered colour or surface. What matters is that the treatment is described honestly.
Are glass crystal balls suitable for scrying?
Yes, and arguably better. Scrying wants clarity and an unbroken surface, which is exactly what optical glass is made for.
Can I cleanse selenite in water?
No. It is water-soluble and water will dissolve the surface. Use a soft dry cloth, and store it away from harder stones so they don't scratch it.
Does a missing hallmark mean my jewellery is fake?
Not necessarily. UK rules set weight thresholds and exemptions, so light pieces can be sold legally unmarked. Check the weight and the description, and ask a jeweller if it was expensive.
What if a listing doesn't explain a treatment?
Ask what the stone is and whether the colour or finish has been altered. A seller who knows their stock will tell you.
Buy with your eyes open
You don't need specialist equipment to be a confident buyer. A few practical checks, a rough sense of hardness, and an eye for the language on the label will get you most of the way.
Natural stones, treated crystals, crafted clusters and glass scrying balls all have their place. They are different things, and the only real problem is confusing one for another.
You can browse the full range of crystals and gemstones, the crystal balls, or read up on individual stones on our crystal meanings pages.
