How to Buy Sapphires: An Unorthodox Guide

How to Buy Sapphires: An Unorthodox Guide

sapphire color study
Hello? Is it me you are looking for? Sapphires are corundums in so many hues.
16ct unheated teal burmese sapphire ring 18k 5f78370f
Hello? Is it me you are looking for? A group of unheated sapphire rings.
intense blue red
Unheated 'sleepy' beauties: vivid 'cornflower' blue, vivid 'pigeon blood' red

Most sapphires in stores or being sold online are heated sapphires, let’s say 90%.
Or 99%.

Heat treatment is a common and age-long tradition. This is legal as long as heat treatment is revealed. These sapphires will still be considered natural insofar as they are earth-mined and are only heated.

Heat treatment is not the same as chemical treatment.

Chemical treatment is an enhancement procedure that should be clearly stated.

Heat treatment has been around for centuries. It is the oldest treatment performed on mined stones. Hence it remains a common treatment performed on stones used in commercial jewelry.

When jewellers ourselves buy gems, our primary concern is always if the stones are earth-mined (not lab-created or synthetic or reconstituted). For much of true luxury jewelry, the ‘natural’ question is actually how ‘natural’ these earth-mined stones are, that is, is the stone heated or unheated?

As a gem or ring shopper, you should ask this question (heated vs unheated). Why?

Here we must digress a little to get to why…

Color vs. Transparency

Unheated emerald cut sapphires.

A typical scenario is this:

There are two blue sapphires you cannot decide on, both are good to high grade, but apart from aesthetics you cannot know which is the stone for you. What is happening?

Usually, when you get a more transparent sapphire, you will sacrifice some color (since more light goes into a less saturated stone). The more transparent a stone, the more light is able to pass through. Yet when a stone is less saturated (ie. not as infused with color), it may have less fire (ie. many times you need color to appreciate fire with your naked eye).

You can see there is a need for balance here, and what matters will depend on your personality (not so much on your preference, since you do not know enough about gems to make an informed statement about your preference)

For the majority of commercially sold gems, probably including the ones you are currently weighing, the more fiery or vivid stone is the heated gem (recall that heat treatment improves clarity and/or color).

Some people like to be able to reflect into the stone, accepting and even liking its subtle inclusions, while some others absolutely must see nothing in the stone.

Three unheated blue sapphires perched on top a 78ct rubellite.
Three unheated blue sapphires perched on top of a 78ct rubellite tourmaline.

Of course you can hunt for the perfect stone, of high transparency and high color. And this explains why such a singleminded approach will lead folks down 3 + 1 roads from here, we jewellers see it so often I believe it’s time we log these scenarios here:

1. Pay too much for a clean, well-cut, but small sapphire (<3ct), or

2. Pay even more for the above that is unheated/natural, or

3. Pay ‘market’ price for a perfect small sapphire (<3ct) that is heated.

4. Let’s skip this until the end.

The Meaning of ‘Market’ Price:
Hunting for a stone that is vivid, clean, well-cut, and well-priced almost always ends with scenario 3, because the search criteria will result in a gem that looks closer to its lab created counterpart: small but perfect, and priced whatever owing to the lack of knowledge of the market (shopper).

This is because after reading a ton of articles (like this) and looking at lust-worthy jewelry online (or ring shopping everywhere), at some hour you would have reached the researcher’s natural exhaustive point, or run out of time and realise you do not care about heated vs unheated. (It is no surprise it is the raison d’être of most dealers to actually buy/sell/price their stones to service this confused ‘market’ price segment who is mostly after a ‘not-too-big-just-perfect sapphire’.)

You tell yourself you will decide on the one stone as long as you do not overpay, for whatever you choose. 

But you will.

This is because no one has told you this:

Own stones that are close to or at least the size of your iris (at least 5ct or thereabouts)

This is a personal wisdom gleaned from studying and staring at stones all these years, and of course, from selling and reselling gems. We operate in a predictably buy-low-sell-high mentality market. This is a fact, if a long-term dealer.

light pink cornflower blue
Sri Lanka Unheated Stones: sought after palettes of a 8.01ct Padparadscha Sapphire & 9.5ct Cornflower Blue Sapphire
peacock blue orange red
Madagascar Unheated Stones: unique colors of Peacock Blue & actual Orange Red Sapphire

The ‘iris’ ethos is only a practical one: a gem must be big enough to gaze within. The human eye needs a stone about its own size (the pupils) to appreciate that other world within the stone. Smaller than its own size, it is hard for the unassisted human eye to lock in aspects of the stone beyond its ephemeral self.

This is why some stones appear to ‘lose’ their color when set into jewelry. Many times a gem may look gorgeous when it is a loose stone but have its color compromised when mounted into gold. Yes, this can happen to any stone, big or small, but it consistently subjects smaller stones to fuzziness.  

It happens quicker than you will admit, before a wistful “I can’t really see the stone”.

Incidentally, our ‘iris’ ethos is supported by what is happening in the gems market, a persistent ‘resale’ market:

Stones have 'investment' value when they are at least 5ct

This is why there is a big jump in the price of sapphires >5ct. Someday when you want to trade in your sapphire for a bigger stone, your first stone will have an actual real value against fickle market preference and valuation, but only if it is unheated.

Of course, many will not bear to part with the first gem, especially if it is the engagement ring, but living with memories does not mean refusing insurance.

If you are investing in your first gem, if you are a lover of stones and/or a jewelry collector, this tip will save you lots of small heartaches for an enduring affair.

We are wry. We can predict by being intuitive about where Mankind’s quest for beauty will go:

Over time, often depletion or else decreased propensity of mines to produce high quality stones, the market will pay anything for unheated stones, perfect or imperfect.  

The Fearsome Window

78.53ct Rubellite
A 78.53ct rubellite tourmaline

A ‘window’ is basically the flat part at the top of the gem. The conventional wisdom (or gospel truth to some) is that the bigger the window, the less fiery the gem.

The thing is, most of us buy gems to set into jewelry. Whatever gem you buy isn’t going to end up looking like what you see under the spotlights in the store. It is the mount that will bring out the beauty of the stone, window or no window, spotlighted or not.

In general, the ‘window’ only matters if a gem is small. For larger stones, go for color (or fire) and admire that in its size!

But the opposite? You would surely cut a small window, if you had a small rough to begin with. 

In reality, how big a window is cut into a stone will depend largely on the circumstance of the rough, lesser on ‘bad’ cutting techniques/decisions.

If the window will not improve the color of a stone, it will not whether it is big, small or smaller.

Under most circumstances, a small window wastes a lot of rough. So if a stone has good color, a cutter will make a decision to preserve the stone’s weight.

Rebel Conclusions

Which brings us to make contentious statements that may appear to go against the grain.

These conclusions are for those who do not believe in timewaste, our sincere refrain:

  1. Budget for an unheated stone, of whatever size you can afford, or else invest in a good and bigger unheated stone, never mind silky inclusions and whatnot as long as you get color.
  2. Do not buy a small, heated, vivid stone. This goes not just for sapphires, but for any gem (I’m talking about you, 1ct Windex blue brazilian paraiba tourmaline).
  3. If you have two to choose, choose the bigger, unheated stone over a ‘perfect’ blue heated stone.
  4. Choose the bigger stone over a smaller stone, even if the bigger stone has a big window and uneven cut.

If you have a good jeweller, they will know how to work that window. It is not a flaw of the stone, unless you will never set the stone into jewelry. As buyers of gems ourselves, we know the window is only a bargaining chip for hagglers. As artistic jewellers, we know the window is only skin-deep and the wearable beauty of a stone will be reflected by the richness of its metalwork.

When is it a good idea to buy a heated sapphire or ruby?

Matched pairs

blue sapphire diamond stud earrings 18k 5ad391b1
A pair of heated royal blue sapphire earrings

We need more of less symmetrical pairs to make earrings.

If you are serious about fire (especially since on the ears much light is blocked), chances are you will have to relax a little on their natural states to source a nice pair without paying double the price for two unheated stones, and two MATCHED stones at that.

In cases for earrings, we could perhaps relax and settle for a well-sized pair of vivid blue sapphires without insisting they be unheated.

More thoughts on matched pairs here.

Calibrated accent sapphires

Baguette Sapphire Window Ring WIP 8
Unique accent stones: unheated, baguette cut, with a sublime 'ink wash' tone - these sapphires, however pale, are hard to procure for many reasons

Calibrated accent sapphires available on the market are almost always heated.

If you manage to find an unheated lot, they are usually in paler colors, or less vivid. Recall that heat treatment is to improve clarity and/or color – if the material is light or pale in color, heat treatment is unnecessary.

Vivid fiery accent stones are always heated material. Why is this so? 

There is just little sense to sacrifice great or good material and cut them into small accent stones when it is way more profitable to cut and sell one or few bigger stones. Hence vivid accent stones are rarely available in meaningful lots to meet demand, any demand.

Then there is the aesthetics of a finished piece of jewelry: if the main unheated stone is so beautiful, it is unlikely a jeweller will resort to using less vivid unheated accent stones just to deliver a wholly unheated jewel. For obvious reasons, a visual whole takes precedence over material integrity. The latter is only if the client insists. 

More thoughts on calibrated sapphires here.

Unusual color palette

17ct tri color sapphire ring men 18k 5f4ba45f
Orange like this and Tri Color like this - unusual if they do not come heated

When the color of a stone is unusual, especially when this stone resides in a design that is hard to replicate.

We can overlook this or that when we are captivated by the off-kilter color of some stones, heated or not. Again, heat treatment is not the same as chemical treatment; as long as the stones are not chemically treated, there is no extraneous material introduced into the stone apart from heat.

The reasoning follows that if these stones are not heated, your eyes may never have been allowed to pick up on their colors in the first place.

For example, unheated ‘orange’ sapphires mostly have an underlying brown tinge, hardly orange to the eyes. Heat treatment removes this tinge, and the best result, though not always like this, is a fiery orange gem as shown above.


blue sapphire lattice cigar ring men 18k 5f80341b
A 10ct heated velvet blue sapphire men's ring with lattice motifs.
Gem Gardener, blue sapphire flower ring, sapphire cocktail ring vintage, blue sapphire cocktail ring, vintage rings singapore, vintage cornflower blue sapphire ring, vintage rings singapore, vintage jewellery singapore, antique jewellery singapore, flower ring singapore
A 5.3ct heated cornflower blue sapphire ring with leaf folds into overall floral form.

Many times it will be hard to replicate a design without spending a lot of time and effort. Many modern pieces of jewelry have interesting work done using heated stones, since affordability is always a factor in the making and selling of commercial jewelry.

The other side to this coin is the allure of antique jewelry. We are no strangers to the ‘antique jewelry’ practice of switching out original old heated or inferior stones for unheated gems in order to have the jewelry appreciate higher in its dollar value.

It is so hard to replicate a design it becomes sensible to put in a ‘worthier’ stone in place of its original.

Fun Projects

A heated blue sapphire and rose cut diamond ring

Sometimes you have a design you want to make/wear without knowing exactly how it will turn out. Sometimes this single ring project will grow to incorporate earrings, pendant and so on. That’s a lot of unheated stones!

These fun projects in life should go easy on your brain and bank. Better fruition than imagination.

It is what it is, Scenario 4:

You end up buying nothing to-day and spend the rest of your life looking for that perfect stone you think is out there, while prices of unheated gems keep going up.

Think Harder
Gem Gardener, pear cut ruby ring, unheated ruby ring, vintage ruby ring gold, ruby ring singapore, ruby diamond ring, ruby halo ring, ruby jewellery singapore
Ruby rings. Only one is heated.

Curiously though, vivid rubies with flux treatment (chemical) are beginning to be very expensive, given commercially available natural unheated or heated rubies just do not have the red desired. What this current trend suggests is rubies will travel the same trajectory as emeralds as time goes by. Like the oiling of emeralds, chemical treatment of rubies will become tolerated by the market as long as it is revealed and beautiful.

In your quest for a beautiful ruby ring are you able to accept a treated ruby, given that prices of pigeon blood rubies, heated or not, are astronomical? Or are you only partial to a heated but not chemically treated rubies?

Star Sapphires

gg star sapphire rings
Blue star sapphires make handsome rings.

Star sapphires are mostly unheated, as heat treatment would destroy the rutile needles that form the star.

In our experience, it is the least transparent sapphires that produce the sharpest stars.

If you are looking to purchase a sapphire, why not consider a star sapphire?

Calibrated Sapphires

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A pair of blue sapphire cluster earrings.

When a design requires calibrated sapphires such as these pear cuts, jewellers have little choice but to use heated gems. This is because using unheated sapphires in this case would require custom cutting them from rough, and that would make a pair of earrings too expensive for most.

You can assume all or most commercially-available jewelry to use heated stones in trendy modern jewelry. Even big names.

Remember it’s not just about getting hold of unheated stones, it is mostly a question of affordability and saleability in what is offered to shoppers, specifically, what they will keenly buy.

Our personal impression is this: fine jewelry has never been so affordable, while modern jewelry has never been so overpriced; both seem to operate in the same market where people just repeat tiresome half-truths. 

Matched Pairs

A pair of 15.74ctw unheated royal blue sapphires

Matched pairs of good sized sapphires command a much higher per carat price than single stones. This is because to produce a matched pair, weight must be sacrificed, and this ‘waste’ must be accounted for.

Let’s say you have one sapphire, and you want to find another one to match it. It is difficult, if not impossible to find one in the same size, shape, and color. So what you will have to do is buy a much larger sapphire and cut it to size.

The next time you see a matched pair of sapphires, don’t ask the dealer if you could just buy one, and be shocked that s/he gives you a price closer to the price for the whole pair!

Beryllium Treatment: The Rise of 'New Heat' vs 'Old Heat'

Beryllium treated sapphires, euphemistically called ‘new heat’, are becoming increasingly common and accepted in the marketplace, as long as it is revealed. This type of color treatment is a chemical treatment that is stable and produces fiery sapphires in myriads of colors. Today even big jewelry houses use them.

It is not hard to imagine a future where the assumption for all commercial jewelry sold will house more affordable ‘new heat’ beryllium infused gems, while more expensive artisan jewelry brands may use ‘old heat’ gems, that is, gems that are heated only but not chemically treated.

These ‘old heat’ gems (that you avoid buying presently) will increase in value much like unheated sapphires today, can you see this happening?

Gemstones, like all the world’s natural resources, are more limited than you can imagine. Falling short, supply will always try to meet demand, while demand will always provide an incentive for ‘creative’ supply. Given that clean, fiery, natural stones cannot be consistently and affordably available, gem suppliers will find ways to provide the market with categorically improved stones to sell something to everyone at every price point.

As we speak, these are some trends we observe:

  1. ‘Heated’ stones will become increasingly expensive, the closer they are to ‘perfect’.
  2. ‘New Heat’ gems will be the norm and affordable to most.
  3. ‘Old Heat’ gems will rival ‘Unheated’ gems, and even more depending on factors such as the origin of stones.
  4. ‘Unheated’ stones will be what it is now, inflated exponentially, year on year.  

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