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Gemstones often undergo numerous treatments that enhance their color and clarity. There are numerous treatments, such as fissure filling, oiling, heating, and so on. Out of all, heat treatment is the most common. About 90% of ruby stone and sapphires undergo heat treatment. When it comes to heated vs unheated gemstones, the right choice largely depends on the type of gemstone you are planning to buy.
While some of you might look for heated gemstones for daily-wear jewelry, others would find untreated gems as their ideal choice for rarity, purity, and long-term investment value. Buying a gemstone is difficult if you are unaware of these terms and their prices. Thus, this blog refers to the real difference between heated and non-heated gemstones. Why does it matter? And which one should you select? We shall get into the glittering world of gemstone treatments and unravel the truth that has been staring us in the face.
Heated gemstone meaning refers to a natural stone that undergoes a heat treatment process to improve its color, clarity, and stability.
This process mimics natural geological heat conditions but is done in a laboratory environment. Heat treatment is permanent and stable. Yellow sapphires are heat-treated to stabilize color. A heated yellow sapphire does not fade in sunlight either.
There are three major reasons:
Some gemstones appear dull in their natural state due to inclusions. Heat treatment reduces their inclusions, allowing light to pass through. Thus, the stone shines beautifully. For instance, natural emerald stone is sourced with inclusions. They are treated to improve color and clarity. Heated emeralds have enhanced color and fewer inclusions.
Read More: A Closer Look at Emerald Inclusions
Heating gemstones intensifies their color. For instance, unheated ruby features red with purplish, bluish, brownish, or even blackish undertones. Heating removes these undertones, making rubies sparkle with an intense red hue.
Learn More: What Color Ruby Is Most Valuable?
Whether you are looking for engagement rings or everyday-wear jewelry, heat-treated gemstones are affordable choices. Improved color and clarity with less price attracts buyers looking for affordable everyday jewelry.
Yes. Heated gemstones are still natural stones formed inside the earth. The only difference is that their color or clarity has been improved through heat. The major difference between heated and unheated gemstones lies in price. Even a small carat weight, an untreated gemstone may cost you much more than a treated gem.
Unheated gemstones are simply what they mean: stones that have not been subjected to artificial heat. They are in the purest form and are as they were discovered in nature. These stones can contain some inclusions, uneven colour, or minor flaws, but that is what makes them so attractive.
Untreated stones are extremely rare. Of the sapphires mined, only 1 in 100 is of good quality and untreated. The scarcity makes them very popular among collectors and connoisseurs.
Yes, unheated gemstones are rare, and that is why they hold investment value.
However, value depends on overall quality. A poorly colored, unheated stone may still be worth less than a beautifully heated stone. So treatment alone does not determine price — quality does. For instance, unheated blue sapphire from the best origins, such as Burma, Sri Lanka, and Kashmir, are highly valuable and command high prices. These stones are purely for collectors.
Read More: Difference Between Heated and Unheated Sapphire How It Affects Sapphire Value?
Visually? No. Even an expert would not be able to distinguish heated from unheated gemstones. This is why it is so important that sellers are transparent. Qualified jewelers will tell you whether a stone has been treated and will give you certification when it is unheated.
A sapphire stone doesn’t need a specific label to be unheated, so you can be certain that it has undergone treatment. It is a business, not a trick--but it is something the consumer ought to know.
Simple Tricks to Identify Heated vs Unheated Gems
Of course, there is the ethical side. The heating of gemstones gives jewelers the ability to utilise stones that would have been thrown away. This minimises waste and utilises additional parts of the natural resources on earth. To that extent, heat treatment is a sustainable practice.
But, when you are a person who appreciates natural, raw beauty and likes to possess a stone that is one in a row, you can use unheated gemstones. Their inclusions and imperfections are as unique as fingerprints — they cannot be replicated.
The right gemstone choice depends on your purpose. Choose Heated If:
Choose Unheated If:
No. Heating does not make a gemstone synthetic or fake. It remains a natural stone from the earth. Fake gemstones are lab-created or imitation materials that are completely different from heat-treated gemstones.
Heat treatment is considered ethical as long as it is:
Whether you are buying the gemstone online or offline, it is important to look for the authentic laboratory certificate. It confirms:
The debate of heated vs unheated gemstones is not about right or wrong — it is about purpose and preference.
Heat treatment is a standard and accepted practice in the gemstone industry. It improves beauty and affordability. On the contrary, unheated gems are rare and significant stones for astrological use. While identifying them visually is a tough task, relying on trusted sellers like Navratan makes the process easier. We deal in almost all precious and semi-precious stones. What sets us apart is the commitment to exclusivity that comes with an authenticated certificate.
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