Heated vs Unheated Sapphires: What You Need To Know

    Heated vs unheated sapphires! That is the question! Does it matter? Should you care? Why do you keep this information on product listings?

    We're chatting about the differences between heated and unheated sapphires, reasons to love them, and what to consider with each type of stone.

    What's the difference between a heated sapphire vs unheated sapphire?

    To the naked eye, absolutely nothing! If you're looking at a sapphire engagement ring and one stone has been heated and one stone has been not - you absolutely cannot tell with the naked eye.

    The difference between a heated vs unheated sapphire - a heated sapphire has been exposed to high levels of heat to improve the appearance the the stone and the saturation of the colors.
    Unheated sapphires are exactly as they came out of the ground - they have not been exposed to any heat.

    What is a Heated Sapphire?

    Most sapphires are heated at extremely high temperatures to intensify their color, remove color-zoning, and improve their clarity. This practice goes back hundredes of years to when sapphires were first discovered and were held to the fire to improve their appearance.

    Unheated Vs. Heated Natural Sapphires

    Reasons to love heat treated sapphires

    Heated sapphires are most sapphires, and we are devoted lovers of sapphires of every kind, both heated and unheated – the mesmerizing deep blues, the aquatic teals, the magical bi-colors. Sapphires are the single most versatile stone with so many color choices and a hardness only beaten by diamonds.

    your heated sapphires questions

    Why are sapphires heated?

    Only about 1% of all sapphires found are of gem-quality without heat treatment.

    If we only used the 1% of sapphires that were naturally of gem-quality, 99% of the gems mined would be discarded. That would not be nearly enough to meet the world's demand. And that would be an incredible waste of Earth's precious resources.

    So, while many sapphire aficionados love the untouched, natural beauty of an unheated sapphire, we also celebrate this natural treatment that allows more gems to be loved and worn.

    Heated Madagascar Sapphire

    is it bad if a sapphire is heated?

    Definitely not. This is a standardized process that doesn’t affect the quality, longevity, or durability of the stone. It’s extremely common and nothing to be concerned about.

    How common are heated sapphires aka heat treated sapphires?

    Heated sapphires are the industry-wide norm. When shopping, you can assume every sapphire has been heated unless it’s specifically labelled as 'unheated'. If a jeweler is certain a stone is unheated or heated, they should put that information on the product listing. If they aren't certain it's been heated or unheated, they will put nothing.

    do sapphires change color when heated?

    A sapphire's color will intensify when its heated - it can darken, lighten, or deepen its original tone.

    Is heated or unheated sapphire better?

    Both heated sapphires and unheated sapphires have their benefits! If you choose an heated sapphire, you'll get a more vibrant, saturated stone for your budget. Also, most heated sapphires are eye-clean, with no inclusions visible to the naked eye. Unheated sapphires will have whatever inclusions were naturally created within them.

    The downside of a heat treated sapphire: They will likely not appreciate in value in the same way as an unheated sapphire.

    Are heated sapphires and unheated sapphires the same price?

    Because an unheated sapphire is more rare, it will command a slight premuim in price over a heated sapphire of the same color and quality.

    Are heated sapphires worth anything?

    Absolutely! Most sapphires on the market are heated and it doesn't negatively impact the value. The small number of unheated sapphires available are worth even more because of their rarity.

    are heated sapphires natural?

    Yes, a heated sapphire just means a natural sapphire was exposed to heat to improve its color and clarity. Synthetic sapphires are not normally heated. Synthetic sapphires can be labelled as:

    • lab created sapphire or lab grown sapphire
    • Synthetic sapphire
    • Imitiation or simulant sapphire

    Is heated blue sapphire good?

    Yes, in fact almost all sapphires (blue and every other color) are heated to improve color and clarity. Having said that, high-quality unheated sapphires are more valuable because they are so rare.

    What are Natural Unheated Sapphires?

    An untreated sapphire is a sapphire in its most natural form. Natural unheated sapphires are mined, then cut and polished into gemstones without any treatment or enhancements.

    Why we love an unheated sapphire

    There’s something so magical about a completely untouched, nature-made gemstone that we just can’t resist. While some of these stones may have more inclusions, they mark that stone’s unique path over millions of years on this planet.

    Unheated stones are also incredibly rare, making up only 1% of all sapphires, and who doesn’t love that? This rarity also adds to their value now and these stones will likely continue to appreciate as their supply decreases.  

    Things to think about with an unheated sapphire

    • Unheated sapphires are more expensive than their heat-treated counterparts. For a comparable-looking stone, you will pay quite a bit more.
    • Unheated sapphires usually have more visible inclusions. Some people love and appreciate these marks of mother nature and others prefer a more flawless finish.
    • Because they are much rarer, it’s more difficult to find a specific stone if you already have something in mind. Having said that, we have many stunning unheated loose sapphires available on the site!

    Unheated montana sapphires

    Some of our favorite unheated sapphires come from Montana where you can find so many naturally bright, vibrant, and uniquely colored sapphires that need no heat treatment to turn heads. Montana sapphires are also considered some of the most responsibly sourced sapphires available with their stingent labor laws, environmental regulations, and transparent mining processes. Read more about how we source ethical sapphires from all over the world in our blog post.

    Peruse all our loose Montana sapphires here!

    non-industry-approved sapphire treatments - LATTICE DIFFUSION

    In this treatment, a sapphire is heated alongside another material like beryllium or titanium. The combination of heat plus the beryllium or titanium changes or intensifies the color significantly. Sapphires diffused with beryllium will be pink, orange, or yellow, and titanium-diffused stones become a bright blue color.

    This process is usually used to make low quality, unsaturated, inclusion-heavy stones into saleable gemstones. These sapphires will cost much less than heated sapphires. This process must be disclosed to the buyer before purchase. We don't sell any of these stones at Gem Breakfast.


    Besides sapphires, heat treatment is the norm for rubies, aquamarine, blue topaz, tourmaline, tanzanite, amethyst, citrine, and blue zircon. Unless they're labeled as 'unheated' you can assume they've been heated to lighten or intensify the color and improve clarity.

    So what's the difference between heated and unheated gemstones & how do you choose?While we love the natural beauty and rarity of an unheated stone, a heated stone will likely have higher clarity and be a more intense color for a lower price - it's all about what matters to you!

    Whether you're looking for loose sapphires, eyeing a sapphire engagement ring, or looking to splurge on a treat-yourself sapphire confection, we're here with all the one-of-a-kind treats!

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