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Bonnot Paris22/9/2026
What colour is sapphire?
Bonnot Paris
April 29, 2026
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5 min read
Bonnot Paris · The Precious Stone Journal 2026
What is the colour of sapphire?
None, in its pure state. What iron, titanium, chromium and vanadium create, the market’s vocabulary, how to assess a hue — and where sapphire ceases to be one.
The colour of sapphire is an accident. A few foreign atoms per million, trapped in a crystal which, on its own, reflects nothing at all.
The title’s question has a counter-intuitive answer: sapphire has no colour of its own. Pure corundum — crystallised aluminium oxide — is perfectly colourless. Everything we see in a display case comes from impurities present in trace amounts.
This article explains this mechanism, then what to make of it in practical terms: how to read the market’s vocabulary, how to assess a hue, and why two stones sold under the same name may have nothing in common. For the complete palette, family by family, our complete colour chart takes over.
01
Chemistry
A colourless
stone
| The mechanism is the same for every shade: a foreign element enters the crystal lattice and absorbs part of the light spectrum. What is not absorbed emerges — and that is what we call the stone’s colour. | Element | What it produces |
|---|---|---|
| Families concerned | Iron + titanium | A charge transfer between the two atoms, particularly effective at absorbing light. |
| Blue, teal | Iron alone | Depending on its proportion, from pale lemon to forest green. |
| Yellow, green | Chromium | Pink — and, combined with orange colour centres, padparadscha. |
| Vanadium | Violet, sometimes accompanied by a colour change depending on the lighting. | Violet |
| Nothing | Corundum remains colourless. We use it mainly as accent stones. | White sapphire |
Two practical consequences follow, and they explain almost everything else in this article. First, colour is never perfectly uniform : impurities are distributed randomly as the crystal grows, producing areas of deeper colour than others. Then, no hue can be reproduced. Two sapphires from the same deposit and of the same weight never look exactly alike.
02
The palette
All except red
This is the phrase we use every day, and it is literally accurate. Sapphire spans the entire spectrum — blue, teal, green, yellow, orange, peach, pink, violet, bicolour, colourless — with one exception, which bears another name.
Iron alone
Green
Without titanium to turn it blue, iron turns the stone green. Long overlooked by the market, this family is returning in the wake of teal — and remains the least sought-after of all, therefore the most accessible at equivalent sizes.
Vanadium
Violet
The least known colour of corundum, and one of the most unstable: some stones shift to blue in daylight and violet under a lamp. Rarer than blue, yet markedly less expensive — demand remains limited.
1.08 ct green sapphire · €852 — 1.60 ct violet sapphire · €1,848. Prices observed in September 2026.
03
The jargon
The vocabulary of blues
The market has named its preferences, and these names determine the price. Be careful, however: they are commercial designations, not measurements. Some laboratories mention them on their reports according to their own criteria; others refuse to do so. None is standardised across laboratories.
The most sought-after
Royal blue
The quintessential electric blue: pure, intense, without grey. It catches the eye even before the setting.
8 808 €
Deep blue
The darker side
A deep blue, brought to life by the radiant cut as it multiplies the facets. Beyond a certain tone, the stone would fade in the evening.
9 552 €
Ceylon blue
The lighter side
The luminous softness characteristic of Sri Lanka, tempered and without harshness. Neither too dark nor so pale that it loses its character.
5 400 €
Loose stones, prices observed in September 2026.
Three terms recur constantly. Royal blue refers to intense, deep blues. Cornflower, or cornflower blue, a lighter, velvety blue. Ceylon blue refers to an origin — Sri Lanka — rather than a precise hue: when claimed, it must be documented by the stone’s report, not by the seller.
The most common misconception
“The darker, the more expensive” is false. A greyish or overly dark blue loses a considerable part of its value, because it fades as soon as the light dims. What the market pays for is an intense blue that remains alive in the evening — intensity must never come at the expense of luminosity.
04
The method
Hue, saturation, tone
The diamond has its four Cs. The sapphire has no equivalent grading scale, but it does have a framework for assessment — the one we apply to every stone, in this order.
01
Hue
The colour family: blue, teal, pink. And the undertones, which matter just as much as the main hue.
02
Saturation
The vividness of the colour. It is the parameter that causes the greatest variation in price, for equal dimensions.
03
Tone
The amount of darkness. Too high, the stone fades; too low, it loses its character.
04
Evenness
Areas of colour, bands, extinction in the corners. Zoning can be a flaw — or a signature.
The test we carry out
Look at the stone in daylight, then in a room lit in the evening. If the colour collapses, we do not select it. It is the only test that matters, and one that no photograph can replace.
05
The boundary
The frontier of red
There is only one clear boundary in this entire spectrum: the one that changes the stone’s name. When chromium becomes concentrated enough to shift the colour into red, the sapphire becomes a ruby.
What makes this boundary fascinating is that it is not clear-cut. The tipping point is debated among laboratories : the GIA places it earlier than the SSEF. Two reports may therefore reach different conclusions about the same gem — one “pink sapphire”, the other “ruby” — with a considerable price difference at stake.
A practical consequence, and one that works in your favour: at comparable quality, a pink sapphire remains significantly more accessible than a ruby. It is the most elegant alternative for those who love red without having the budget for it. Conversely, if it is truly a pure red you are looking for, only a ruby engagement ring will provide it — no pink sapphire, however saturated, will cross the line.
06
The pitfall
What light changes
A stone does not create light: it reflects what it is given. Warm light draws tones towards red, daylight towards blue. The same teal sapphire may appear distinctly blue in a display case and noticeably green by a window.
The phenomenon sometimes goes much further. Certain sapphires, known as colour change, shift from blue to violet depending on the light source. It is spectacular, sought after by collectors, and comes at a price.
Hence the rule we repeat at every appointment: never choose a shade on a screen. No screen is calibrated like yours, and no photograph can reproduce a stone’s behaviour under different lighting conditions. This is why we film each gem in several lights, on a neutral hand and with no colour retouching whatsoever.
To go further
The ten colour families, with thirty real stones, their shade codes and the corresponding ring, are brought together in our complete sapphire colour chart. It is the natural continuation of this article.
03
The colour chart
The colour chart: nine families, thirty-six shades
Each shade below was sampled from a photograph of a stone actually displayed in our window. Nothing is chosen from a palette: these are the colours of our gems, extracted one by one.
Shades recorded from our in-stock stones, September 2026. Prices include VAT. Per-carat averages apply to stones from 0.9 to 2.5 ct across the entire stock; the number of stones shown corresponds to the ring sizes available on the date of recording.
What a swatch does not say
Each swatch is an average. It works for a clear, even colour; it fails for a very pale shade or for a crystal containing two. And above all: a screen cannot convey a gemstone. These colours provide a direction, not a promise.
04
Reading it
What this colour chart reveals
Three lessons can be read directly from the bands above.
There is no break between the families. Blue shifts towards teal, teal towards green, green towards yellow. Names are conventions placed upon a continuum — and the boundary stones, those that refuse to be named, are often the most interesting to look at.
The price gap does not reflect geological rarity. Violet is rarer than blue and costs €1,150/ct versus €1,780. Yellow, at €990/ct, is the most accessible family in the colour spectrum without being any less hard or beautiful. What you pay extra for in a blue is reputation.
Only one family plays in a different league : padparadscha, at €2,850/ct, nearly three times the price of teal. As its designation is controlled by an independent laboratory, an appealing orangey-pink without mention in the report remains a pink sapphire — which mechanically limits supply.
| Family | Median price per carat | Position |
|---|---|---|
| Padparadscha | €2,850/ct | Controlled designation: limited supply |
| Blue | €1,780/ct | Demand, more than rarity |
| Pink | €1,500/ct | Chromium, as in ruby |
| Green | €1,200/ct | Making a comeback |
| Violet | €1,150/ct | Rarer than blue, half the price |
| Teal | €1,010/ct | The most abundant family |
| Yellow | €990/ct | The most accessible in the colour spectrum |
Medians recorded across 262 stones of 0.9 to 2.5 ct, Bonnot Paris stock, September 2026. Orange and bicolour are not included in this ranking: their samples are too limited to produce a reliable median.
07
Frequently asked questions
Sapphire colour, your questions
What is the natural colour of sapphire?
None. Pure corundum is colourless: all colours come from trace impurities — a few atoms per million. Iron and titanium produce blue, iron alone produces yellow and green, chromium produces pink, and vanadium produces violet.
Can a sapphire be other than blue?
Sapphire comes in every colour except red: blue, teal, pink, padparadscha, yellow, orange, peach, green, violet, bicolour, and even colourless. When chromium becomes concentrated enough to shift the stone into red, it changes name and becomes a ruby.
What do royal blue and cornflower mean?
They are commercial shade designations: royal blue for an intense, deep blue; cornflower or cornflower blue for a lighter, velvety blue. They are not standardised between laboratories — some mention them according to their own criteria, while others do not — and they strongly influence price.
How should colour be assessed?
By its hue, saturation, tone and uniformity. A stone that is too dark loses its brilliance as soon as the light fades; a stone that is too pale loses its character. A fine sapphire retains its colour in low light — that is the only test that matters.
Is a dark blue of better quality?
No. A greyish or overly dark blue loses a considerable part of its value. What the market seeks is an intense blue that retains enough light to remain vibrant in the evening: intensity should never come at the expense of luminosity.
Why does colour change with the lighting?
Because the stone reflects only what the light gives it: a warm source pulls towards red, daylight towards blue. Certain so-called colour-change sapphires shift distinctly from blue to violet depending on the source. No screen can replace holding the stone in your hand.
Where does pink end and red begin?
With the concentration of chromium, and nothing else. The tipping point is debated between laboratories: the GIA places it earlier than the SSEF, and two reports may reach different conclusions on the same gem. If it is a true red that you are looking for, only a ruby engagement ring will provide it.
How many colours can sapphire take on?
All of them, except red. We work with ten families: blue, teal, pink, padparadscha, violet, yellow, green, orange, peach and bicolour. When the concentration of chromium becomes strong enough to shift the stone into red, it changes name and becomes a ruby.
Which colour is the most expensive?
Padparadscha, by a clear margin: around €2,850/ct as a median value across our stock, compared with €1,780 for blue and €1,010 for teal. Its designation is controlled by laboratories, which mechanically limits supply.
Which colour is the most accessible?
Yellow and teal, at around €1,000/ct in median value, followed by violet and green. These families are less sought-after than blue without being any less beautiful or durable: the same hardness of 9 out of 10.
What is a padparadscha?
A sapphire combining pink and orange in roughly equal parts. It is the only sapphire to bear its own name, derived from the Sinhalese padmaraga which refers to the lotus flower, and the only one whose designation is controlled by laboratories. Without mention on the report, a pinkish-orange stone remains a pink sapphire.
The colours, set in rings
The loose stones in this guide, with their full characteristics, can be browsed from the page sapphire.
Colour is judged in hand
Two stones side by side under the same light, then the same comparison in the evening: a colour is decided in three minutes. In Paris, or by video under several lighting conditions.
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