Why Unheated Sapphires Reign Supreme

Why Choose Unheated Sapphires?

Authenticity: The New Luxury

Unheated sapphires represent an ultimate expression of natural beauty. Free from thermal enhancement, they retain their original brilliance and depth, making them the ultimate choice for discerning collectors and investors. With over 95% of sapphires undergoing heat treatment, fine-quality unheated stones—especially those with rich, vivid hues are hard to come by. This scarcity commands a premium in the market, reinforcing their status as coveted assets with strong long-term appreciation.

Consumers increasingly demand authenticity and transparency in their purchase decisions. In many ways, unheated sapphires represent a shift in luxury values—prioritising integrity, provenance, and a deeper connection to nature over human enhancement. While there’s certainly nothing wrong with purchasing heated sapphires, transparency about treatments and appropriate pricing remain essential considerations.

Similarly, heirlooms once seen as symbols of wealth, now hold deeper sentimental value and natural integrity. As a result, unheated sapphires represent emblems of this modern luxury, cherished as family treasures passed down through generations.

Jewellery brands today are adapting to this evolution too, shifting their sourcing, production, and storytelling to align with these values. Only 5% of sapphires used in jewellery remain completely unheated. This rarity has attracted lifelong dealers like Joe Belmont, Founder of KV Gems, to specialise exclusively in unheated gems—not just for their rarity and value but out of a deep appreciation for their untouched beauty.

“I’ve always believed unheated sapphires are more beautiful than heated ones,” he explains. “They retain a certain moisture that enhances their brilliance, whereas heating dries them out, diminishing their lustre. Unheated sapphires are rarer, completely natural, and straight from Mother Earth. I believe there is power in them.”

Exclusive Appeal: Finding the Perfect Match

While unheated single stones are rare, matched pairs—nature’s twins—represent extraordinary exclusivity. Unlike heated stones with their uniform appearance, unheated sapphires showcase unique variations in hue and character, making perfectly matched pairs scarce.

With the finest sapphires appearing in countless variations of colour and cut, finding a perfect layout for a jewellery suite becomes a thrilling challenge requiring expertise, patience and a bit of luck. To meet this demand, KV Gems continuously expands its inventory to create matched sets and design layouts.

“Finding a matching set of unheated royal blue sapphires, even in 1ct sizes, is incredibly challenging,” says Maria Belmont, Director of KV Gems explains. “This makes a jewellery piece even more rare and unique.”

Established Market Presence

According to recent auction data, the market for rare, gem-quality coloured stones remains robust, consistently performing well at jewellery sales, with exceptional specimens commanding premium prices.Natural sapphires of exceptional quality and significant size are becoming increasingly sought-after collector items as viable sources continue to diminish globally.

Unheated sapphires have consistently demonstrated their value and desirability in the high-end jewellery market. A standout auction result in May 2023 at Phillips highlighted the enduring appeal of natural unheated gemstones. A sapphire and diamond necklace by Bulgari, featuring a remarkable 118.35-carat unheated Ceylon sapphire, sold for HKD 26.8 million (USD 3.4 million).

Natural sapphires of such exceptional quality and significant size are becoming increasingly sought-after collector items as viable sources continue to diminish globally. “The finest and most beautiful treasures, like unheated sapphires, not only hold their value but increase it over time,” says Belmont. “Our clients appreciate the extraordinary, where each sapphire is irreplaceable. We collaborate with independent jewellers and brands that source unheated sapphires to complement their designs.”

Every unheated sapphire deserves exceptional craftsmanship to elevate its natural beauty. In the realm of contemporary jewellery design, several designers, ateliers and high jewellery maisons embrace the unique characteristics of unheated sapphires, allowing their natural essence to guide their creative vision. How a gemstone is set, shaped, and styled not only enhances its inherent qualities but transforms it to heirloom status. The spectrum of colours, from classic royal blue to rare pastel hues, provides designers with a rich palette for their creations, and often paired with diamonds and set in 18K gold or platinum truly honour the gem’s beauty.

Should you buy unheated sapphires at a premium?

The question of whether unheated sapphires justify their premium price depends on understanding their true value proposition. While these gems often command significantly higher prices than their heated counterparts, their ‘investment’ potential requires careful consideration beyond the allure of rarity.

An unheated sapphire’s value is defined by its uniqueness, beauty and scarcity—determined through the following factors. Firstly, the traditional 4C’s—(colour, cut, clarity and carat weight) establish the foundation. Secondly, is the sapphire unheated, and does it come from a historical geographical origin? Finally, the cut must strike the perfect balance between weight retention and optimal brilliance, allowing the sapphire to showcase its full colour, clarity, and beauty.

“Collectors should always consider quality first—clean stones, no zoning, excellent cutting in unheated sapphires [corundum] will only become harder to find,” explains Belmont.

While the grand headlines at auctions can be captivating, navigating the gemstone market purely as an investment requires careful consideration. While some stones have indeed gained value, like any asset, buying unheated sapphires at a premium requires a thorough understanding of market dynamics, rarity, and the various factors that influence value—geopolitics, economic trends, supply chain shifts, consumer demand, and even cultural preferences. Diving in without proper knowledge can be a risky endeavour.

“The term ‘investment’ can be tricky; I wouldn’t recommend anyone invest in gemstones without a solid understanding of the market,” cautions Maria. “A fine unheated sapphire is rare to find and requires expert guidance on quality, certification, and provenance. Always buy from a reputable dealer you know and trust.”

Modern Premier Sources

Sapphires from now-closed mines like Kashmir and Myanmar are highly prized for their rarity and historical significance, often commanding extraordinary prices at auction. The Kashmir mine, known for its vivid blue sapphires, has long been regarded as one of the most coveted sources, though it ceased production in the early 20th century. Similarly, Myanmar (formerly Burma), once a leading source of unheated sapphires, has seen a decline in production due to political and regulatory changes. With unheated sapphires from Burma and Kashmir becoming increasingly scarce, those from Ceylon (Sri Lanka) and Madagascar have emerged as high-quality alternatives.

Sapphires have been mined in Sri Lanka for over 2,500 years —far longer than Burma. Known for their medium to deep cornflower blue hues and distinctive silky texture, these sapphires have remained a staple in the fine jewellery world. Unheated Sri Lankan sapphires consistently command higher prices than their heated counterparts of the same size and quality, reflecting their rarity and natural beauty.

Several unheated Ceylon sapphires at Phillips’ May 2024 auction notably outperformed their estimates. A sapphire and diamond ring featuring an 18.01-carat step-cut Ceylon sapphire with no indications of heating (Lot 351) was estimated between CHF38,000 and CHF55,000, but it sold for CHF196,850, far exceeding its high estimate. Meanwhile, a Harry Winston sapphire and diamond necklace (Lot 410), which included a 5.30-carat unheated Ceylon sapphire, was expected to fetch between CHF145,000 and CHF235,000. It sold for CHF190,500, falling within its estimated range. These results underscore the premium associated with unheated Sri Lankan sapphires, particularly those of notable size and quality, highlighting their superior value in the gemstone market.

Madagascar has also emerged as a prominent source, with some of its finest sapphires steadily gaining a strong foothold in the high-end gemstone market, following major discoveries in the 1990s and the 2016 rush at Bemainty. These finds have reshaped the high jewellery landscape, providing a new source of exceptional sapphires that rival historical sources like Sri Lanka and Burma. These discoveries have not only expanded the supply of fine unheated sapphires but have also been embraced by prestigious jewellery houses. A prime example is Bulgari’s sapphire and diamond necklace, featuring nine unheated Madagascan sapphires, which achieved an impressive sale price of approximately US$1.03 million at Christie’s. This exemplifies Madagascar’s growing influence in high jewellery, proving that rarity and beauty—not just historical origin—define today’s most sought-after gems.

Recent auction data also suggest the growing demand for Madagascar sapphires, reflecting their increasing value and market appreciation. A pair of unheated Madagascan padparadscha-like sapphire earrings first sold at Phillips in 2014 and later at Sotheby’s in 2019 achieved approximately 25% increase in value—demonstrating growing collector recognition and potential return for these stones.

While past auction results demonstrate strong demand, prospective buyers should always approach with eyes wide open, by conducting thorough due diligence. As buyers navigate this dynamic market, it’s essential to strike a balance between certification and aesthetics. While provenance and lab reports offer vital context, it is the visual appeal of a sapphire—its colour, clarity, and overall presence—that ultimately determines its value. The market’s preoccupation with geographic origin often overshadows what truly matters—a gem’s inherent beauty and rarity, which transcends both geography and fleeting trends.