Tag: materials

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Green Fluorite: A Closer Look

Green fluorite is the stone people pick up and turn over in the light. It is one of the few materials in our collection that changes noticeably as you move it: a bead that reads flat mint from one angle can show a seam of deeper green, or a drift of colourless glass, from another.

It is also one of the softer stones we work with, which shapes how it is cut, strung and worn. Here is what that means in practice.

What green fluorite is

Fluorite is calcium fluoride, a mineral that forms in cubic and octahedral crystals. It occurs in a wide range of colours — purple, blue, yellow, colourless — and green is among the most common. The colour comes from trace elements and structural quirks in the crystal, not from any treatment or dye in the material we use.

Its most recognisable feature is transparency. Good green fluorite is glassy rather than stony, and light travels some way into a bead before it stops. Held against a window, a well-cut round can look almost like a drop of water with green suspended in it.

Colour banding

Fluorite grows in layers, and those layers often differ in colour. When a bead is cut from a crystal, the cut runs across those layers and the banding shows up on the surface of the sphere as stripes, wedges, or soft gradients.

This is why no two beads on a fluorite bracelet look the same. On a single strand you might see:

  • Beads that are almost uniformly pale green, with only a faint clouding
  • Beads with a clear band of saturated green running through the middle
  • Beads that shade from green into colourless, sometimes with a hint of blue or purple at one edge
  • Small internal fractures that catch light and read as a flash or a fine seam

Those internal features are normal in fluorite, not faults. We sort beads for tone and place them along a strand so the colour moves in a way that looks intentional, rather than trying to match every bead to a single shade. That sorting is done by eye, by hand, at the bench in Xingyi — you can see how it comes out across the current pieces in the Mistfell shop.

Why it is handled carefully

Fluorite sits at 4 on the Mohs scale of hardness. For comparison, quartz — including amethyst — sits at 7, and window glass is around 5.5. Fluorite is soft enough to be scratched by a sand grain, a steel key, or a harder stone in the same drawer.

It also has perfect cleavage in four directions, meaning the crystal has natural planes along which it parts cleanly. A sharp knock in the wrong direction can chip a bead along one of those planes rather than simply scuffing it.

That affects the whole process. Drilling is slow. Beads are checked individually before stringing, because a hairline chip near a drill hole is easy to miss and difficult to live with later. Finished bracelets are packed so the beads are not pressed against each other in transit.

Wearing and keeping it

None of this makes fluorite delicate to the point of being impractical. It makes it a stone to be slightly deliberate about.

  • Store it on its own, or in a soft pouch, rather than loose with harder stones and metal
  • Take it off for washing up, gardening, gym work, and anything with grit or knocks involved
  • Clean it with a soft dry cloth, or a barely damp one; skip ultrasonic cleaners and household chemicals
  • Keep it out of long, direct sun, which can dull the colour of some fluorite over time

Worn on the days it suits and put away on the days it does not, a fluorite bracelet holds its surface well. Our pieces are made in small numbers by named makers, and the strand in the photograph is the strand that arrives — banding, seams and all. They are also available to buyers worldwide through our Etsy shop.

Questions & answers

How hard is green fluorite, and does it scratch easily?

Fluorite is 4 on the Mohs scale, softer than quartz (7) and window glass (about 5.5). It scratches fairly easily, so it is best stored separately from harder stones and metal jewellery.

Why do the beads on a green fluorite bracelet look different from each other?

Fluorite grows in coloured layers, so each bead is cut across a different part of the crystal. Variation in tone, banding and clarity between beads is normal and expected.

How should I clean a green fluorite bracelet?

Wipe it with a soft dry or barely damp cloth. Avoid ultrasonic cleaners, hot water, and household cleaning products, and remove the bracelet before washing up or using hand sanitiser.

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Turquoise and Its Look-Alikes: A Buyer’s Guide

Turquoise is one of the most imitated stones in the bead trade. It is soft, porous and often sold in small quantities, which makes it easy to substitute and hard for a buyer to check. Most of what is described as turquoise on open marketplaces is something else: dyed howlite, dyed magnesite, or reconstituted powder pressed back into a bead.

None of these substitutes are dishonest in themselves. Dyed howlite is a perfectly good blue bead, and reconstituted turquoise does contain turquoise. The problem is only ever what a piece is called. This is a guide to telling them apart.

What natural turquoise looks like

Natural turquoise is a copper aluminium phosphate. It forms in dry, mineral-rich ground, filling seams and cavities in host rock, which is why so much of it carries matrix — the veining or webbing of the surrounding stone, in brown, black, rust or grey.

Some markers of untreated material:

  • Colour that varies across a single bead, and from bead to bead in a strand. Turquoise is rarely uniform.
  • Matrix that reads as part of the stone rather than sitting on top of it. Veining should continue through the bead and around its curve, not stop at the surface.
  • A waxy to slightly dull lustre when polished, rather than a glassy shine.
  • Real weight. Turquoise is denser than howlite or magnesite and feels heavier in the hand than it looks.

Dyed howlite and magnesite

Howlite is a white borate mineral with fine grey or black veining. Magnesite is a white carbonate with a similar look. Both are cheap, widely available and take dye readily, which makes them the standard turquoise substitute.

Dyed material tends to give itself away in a few ways. The blue is often flat and even across every bead in a strand — a consistency natural turquoise seldom achieves. Colour pools darker in the drill hole and in surface cracks, where dye has collected. The veining is grey or black and rather uniformly spidery, without the rust and brown tones that iron in the host rock produces. And the beads feel light.

Held next to natural turquoise, the difference is usually obvious. Held alone, it is not, which is why the labelling matters.

Reconstituted and stabilised stone

These two terms are often confused, and they are not the same thing.

  • Stabilised turquoise is natural turquoise that has been impregnated with clear resin to harden it and stop it absorbing oils. The stone is intact; the resin fills its pores. Most turquoise on the market is stabilised, and reputable sellers say so. It is still turquoise.
  • Reconstituted turquoise is turquoise dust and fragments — often offcuts from cutting — mixed with binder, dyed, and pressed into a block that is then cut into beads. The material is turquoise-derived but has been remade.
  • Imitation turquoise may contain no turquoise at all: dyed howlite, dyed magnesite, resin, ceramic, or plastic.

Reconstituted beads often show a very even texture with tiny flecks distributed too regularly, or a faint seam where the block was cut. The colour is uniform in a way that looks convincing in a photograph and less so in the hand.

Practical checks before you buy

  • Read the wording. “Turquoise colour”, “turquoise style” and “howlite turquoise” all mean not turquoise. A seller who deals in the real thing will name it precisely and mention stabilisation.
  • Look at the price against the size. Natural turquoise in larger bead sizes is not cheap, and a wide strand of uniform 10mm beads at a low price is telling you something.
  • Ask for the photograph of the actual piece rather than a stock image. Variation between beads is easier to judge on a real strand.
  • Look at the drill holes in close-up. Dye concentration there is one of the more reliable signals.

How we handle it

Turquoise appears in our collection alongside amethyst, nanhong agate, green agate, green fluorite and moonstone. Every piece is strung by hand in Xingyi, in the karst highlands of Guizhou, by makers we name — Wu Yunhua and Fanfan among them. Beads vary; that variation is why we do not photograph one bracelet and send another. You can see what is currently available in the Mistfell shop, where the piece in the photograph is the piece that arrives.

If a stone is stabilised, or if a strand is not turquoise at all, the listing says so. That is the whole of it.

Questions & answers

How can I tell if turquoise is real or dyed howlite?

Look for uneven colour across the beads, matrix veining that runs through the stone rather than sitting on the surface, and real weight in the hand. Dyed howlite is light, evenly coloured, and shows dye pooling in the drill holes and surface cracks.

Is stabilised turquoise still real turquoise?

Yes. Stabilised turquoise is natural stone impregnated with clear resin to harden it. The turquoise itself is unaltered in composition. Reconstituted turquoise is different — it is powder and fragments bound and pressed into a block, then cut.

Why is natural turquoise more expensive than the blue beads sold as turquoise?

Natural turquoise is mined in limited quantities, much of it too soft or thin to cut, so usable material is a small fraction of what comes out of the ground. Dyed howlite and magnesite are common minerals and cost a fraction as much.