Treated vs. Untreated Sapphires - Why Choose Natural Untreated Sapphires?

There are three primary reasons to choose natural untreated sapphires: they are beautiful, rare, and valuable. These three attributes are clearly connected; the interaction of the first two factors produces the third. Let us consider each element of the equation separately and you will see why untreated sapphires add up to a smart decision.


Whether they sparkle, glow, or shine, gemstones have been used in jewelry for centuries because they please the eye. When the first jewelry pieces were crafted, there were no alternatives to an authentic gemstone. Synthetics and stimulants simply did not exist. If appearance is your only concern, then you might consider an honest fake. “Costume jewelry” pieces and synthetic stones will not have the subtle variations and uniqueness of real gemstones, and while they may look nice, they are neither rare nor valuable.

If appearance is your only priority, you might choose to stop reading here. If, however, you are interested in "the real thing," it is important to know the factors you should consider when shopping for natural sapphire jewelry.


If the streets were lined with gems, we would not consider them items of great value. It is their scarcity, as well as their beauty, that captivates us. We are attuned to appreciate objects that are uncommon and unusual, and to cherish the standouts of the bunch. Once a gemstone is set into jewelry it becomes an even more powerful symbol of value; it recognizes the uniqueness of the wearer.

Once an item is identified as rare, one must understand the nature of that item in order to properly judge its value. Coal and diamonds are both forms of pure carbon. But, it would be incorrect to say a piece of coal is rare just because its chemical makeup is the same as a diamond. Sapphires and rubies are composed of the mineral corundum. But, not all corundum is rare. For example, you can buy black corundum in the form of emery sandpaper at the hardware store. A gem-quality untreated sapphire or ruby is exceptional because of its natural color and clarity.

Treated vs. Untreated

Before and after examples of beryllium treated sapphires

Most people are unaware that almost all sapphires are heated at extremely high temperatures to "enhance" their color and clarity. Very low grade sapphires are also treated with chemicals to alter their color, transforming stones that would not be market grade into saleable pieces. These processes may increase the stone’s beauty, but not its value. A sapphire can be listed as “natural” simply because it is not lab created. However, “natural” does not mean the sapphire has not undergone any alterations. The key term is “untreated,” meaning a sapphire is natural (not lab created) and has not been subject to any chemical or heat treatments. Approximately only 0.5 - 1% of the sapphires discovered are of gem quality without treatment. Natural untreated sapphires are far more uncommon and valuable than treated and chemically altered stones.

You might ask, “What's wrong with a little enhancement? It’s just an improvement….” For something to be rare, it needs to be in its original condition. Consider a piece of antique furniture. Its finish may be worn, but it is still as detailed as it was when it was first crafted. You could refinish the piece to improve its look, but any antique dealer would tell you that it would greatly devalue the item because it would no longer be in its original condition.

rough blue sapphire crystals

The Global Gemstone Market

Now that much of the world has been explored, gemologists and jewelers have a good handle on what items are rare in the gemstone world. Occasionally new mines are discovered, but overall the abundance of each gemstone type is well understood. There was a time when this was not the case. A century ago diamonds were very rare, and hence, they were very valuable. When large and abundant diamond deposits were discovered in Africa, those in the diamond business recognized that the value of diamonds would plunge if the new stones were released into the market. On a global scale diamonds were not that uncommon, and in order to keep their prices artificially high, a cartel was formed that to this day still controls the flow of the majority of diamonds.

As new non-cartel mines open, and the taboo of selling personal diamonds weakens, the prices of diamonds could drop to reflect their true value and lack of rarity.

In contrast to diamonds, untreated sapphires remain extremely uncommon, and are growing rarer with the passage of time. As more people learn the truth about sapphire treatments and the real value of untreated stones, prices will only increase.

Color and Clarity

Silk inclusions in an untreated sapphire (viewed under magnification)

The selection process for a sapphire does not end with the decision to buy an untreated stone. The most important contributing factor in a sapphire's beauty is its color. Sapphires are known for their blue hues, but they come in a wide range of colors, and the choice of color is highly personal. The rich, deep, and pure colors are considered the most rare and valuable.

A stone's color is best revealed by the choice and quality of its cut. The quality of a stone’s cut is extremely important and can vary greatly as to how well it succeeds in revealing the full potential and beauty of the sapphire. A well cut stone demonstrates great play-of-light throughout the sapphire, showing off its color and sparkle.

The clarity of a sapphire is important as well. Natural untreated stones will usually have more inclusions than treated sapphires. The many types of treatments performed on sapphires will not only alter their color, but also their clarity. Inclusions should not always be seen as negative attributes in untreated sapphires. In most cases, they are undisputed evidence that the sapphire has never been treated. The best option is to seek an untreated stone with minimal visual inclusions, but enough that it can be correctly identified as natural and untreated.

A sample GIA certificate


Another major consideration when buying untreated sapphires is authenticity. The changes that result from heating can be dramatic to the eye, but subtle to the stone internally. It is important to be sure of what you are buying. There are two things you can do to ensure that the stone you are purchasing is genuine.

First, insist on a certificate from an independent gemological laboratory. These contain basic information about the sapphire and document any indications of heat treatment. Second, only conduct business with a highly reputable company with specific knowledge and expertise concerning untreated sapphires. A reputable company may be able to deal directly with the miners, meaning that the sapphire will go right from the mine to the cutter - skipping any ovens.

Finally, you must see a sapphire to fully appreciate it. Gems do not always photograph well, and it is the interaction of light with the stone is what makes it beautiful. You should look at enough choices so that one will stand out to you. Be sure to look at your stone under various types of lighting conditions to see the variations of color that the sapphire reflects. White florescent light and direct sunlight will show the true color of a sapphire the best.

Before and after examples of beryllium treated sapphires

In Conclusion

Understanding what you are purchasing is the first step in making an informed and secure decision. A fine untreated sapphire meets all of the expectations of what a gemstone should be: truly rare, stunningly beautiful, and valuable in every sense.