Growing scarcity is changing the coloured-gemstone market. A Financial Times report published on 4 September 2026 describes how mine closures, depleted deposits, environmental pressures and political disruption are restricting supplies of several traditionally important stones.
At the same time, collectors and jewellery designers are looking beyond the familiar combination of diamond, ruby, emerald and blue sapphire. Paraíba tourmaline, spinel, garnet, tanzanite, peridot and other distinctive gems are receiving greater attention—not merely as substitutes, but as important gemstones with colours and qualities of their own.
Why are some gemstones becoming scarcer?
Every natural gemstone depends upon a particular combination of geology and geography. Commercial deposits can be confined to a small number of locations, and even an established source may produce relatively little material of fine jewellery quality.
Mines eventually become depleted or uneconomic. Production can also be interrupted by changes in regulation, political instability, conflict, environmental damage or the practical difficulty of working remote deposits.
The effect is most pronounced when a particular source is associated with an exceptional colour. Brazil’s original Paraíba tourmaline deposits produced extraordinarily vivid blue and green stones coloured by copper. The Batalha workings are now largely exhausted, while production from other deposits remains limited.
Australia’s Argyle mine, once responsible for the majority of the world’s pink-diamond supply, closed in 2020. Although pink diamonds occur elsewhere, the distinctive Argyle material can no longer be replenished through continuing production from that mine.
The rise of Paraíba tourmaline
Paraíba tourmaline is among the most dramatic examples of a gemstone moving from relative obscurity to international prominence.
The first important material was discovered in the Brazilian state of Paraíba during the late 1980s. Its intense electric-blue, turquoise and green colours appeared to glow from within, distinguishing it from conventional tourmaline.
Later discoveries in Nigeria and Mozambique produced copper-bearing tourmalines with related colours. Laboratories may be able to investigate geographical origin, but appearance, copper content, size, clarity and quality can all influence value.
The Financial Times reports that prices for some Paraíba tourmalines increased by as much as 45% during the past year. An exceptional example sold at Christie’s in New York during 2025 for approximately $311,000 per carat.
Those figures concern the very top of an unusual collector market. They should not be treated as a general valuation for every blue-green tourmaline carrying the Paraíba name.
Spinel steps out of ruby’s shadow
Red spinel was mistaken for ruby for centuries because the two gemstones can display remarkably similar colours and occur in some of the same deposits.
Several celebrated “rubies” in historic royal collections were eventually identified as spinels. The Black Prince’s Ruby in the Imperial State Crown is perhaps the best-known British example.
Modern gemmology clearly distinguishes the two minerals, allowing spinel to be appreciated under its correct identity. Fine red stones remain highly desirable, while cobalt-blue, pink, purple and grey spinels have widened the gem’s appeal to contemporary designers.
The strongest spinels can possess vivid colour and excellent brilliance without requiring the same treatments commonly encountered in parts of the ruby market. This does not make every spinel rare or valuable, but exceptional stones are no longer regarded simply as inexpensive alternatives.
According to the Financial Times, prices at the upper end of the spinel market have risen substantially over the past decade.
Garnet offers more than dark red
Garnet is another gemstone family whose variety is easily underestimated. The name describes a group of related minerals rather than a single uniformly coloured stone.
Traditional red varieties remain familiar, but garnets can also be orange, pink, purple, green and combinations of these colours. Mandarin garnet is prized for its intensely bright orange, while tsavorite garnet can display a rich green comparable with fine emerald.
Demantoid garnet is especially admired for its brilliance and dispersion—the separation of white light into spectral colours. Fine examples may show more coloured fire than diamond, although their different hardness and wear characteristics must be considered when choosing a setting.
These gems allow jewellery designers to work with distinctive natural colours without imitating ruby or emerald. Their appeal lies in being recognisably different.
Unheated sapphire becomes increasingly desirable
Sapphire itself is not a newcomer, but growing interest in unheated examples reflects the wider search for rarity, provenance and individual character.
Heating has been used within the gemstone trade for many years to improve or stabilise colour and clarity. It is an accepted treatment when properly disclosed and does not make a sapphire artificial.
An attractive unheated sapphire is rarer because its colour and appearance have not been improved through this process. Laboratory evidence supporting the absence of heat can therefore add a premium, particularly when combined with an important geographical origin.
Buyers should not assume that “unheated” automatically means beautiful. Colour, tone, transparency, cut and overall appearance remain essential. A well-chosen heated sapphire may be more attractive than an untreated stone selected solely for the wording on its report.
Why “semi-precious” is becoming outdated
The traditional language of “precious” and “semi-precious” divided diamond, ruby, sapphire and emerald from almost every other gemstone. That distinction says little about a stone’s actual beauty, rarity or value.
An exceptional Paraíba tourmaline, spinel or demantoid garnet may be considerably rarer and more valuable than an ordinary example from one of the traditionally precious categories.
The expression can also give the misleading impression that an entire gemstone species occupies one level of quality. In reality, value varies enormously within every category.
Colour, clarity, cut, size, durability, origin, treatment and market demand must all be considered. Describing a gemstone accurately by its proper name is more informative than assigning it to a broad historical hierarchy.
What buyers should check
Unfamiliar gemstones make accurate identification especially important. Similar colours do not necessarily indicate the same mineral, origin or treatment.
A reputable independent laboratory can establish a stone’s identity and disclose detectable treatments. For certain gemstones, it may also provide an opinion on geographical origin, although origin determination is not possible in every case.
Buyers should ask whether the gemstone is natural, whether it has been treated and whether the seller’s description is supported by reliable documentation. They should also consider how it will be worn.
Sapphire, ruby, spinel and many garnets can be suitable for frequently worn rings when correctly set. Tourmaline, tanzanite and kunzite require more thoughtful handling because they may be more vulnerable to knocks, scratching or cleavage.
Rarity does not remove the need for practicality. A gemstone chosen for an engagement ring must be capable of coping with a very different life from one placed in an occasional pendant.
Scarcity does not guarantee an investment
Rising auction prices can encourage gemstones to be presented as investments, but the market is highly specialised.
Coloured stones are not standardised commodities. Two gems of identical variety and weight may differ markedly in colour, clarity, treatment, origin and cut. These differences affect desirability and make simple price comparisons unreliable.
Auction records generally concern outstanding specimens with exceptional size, provenance or quality. They do not establish what an ordinary owner could obtain when reselling a commercial-quality stone.
Jewellery is best purchased to be worn and enjoyed. Rarity and enduring demand may help support the value of an exceptional gemstone, but neither provides a guaranteed financial return.
A broader and more colourful future
The increasing prominence of alternative coloured gemstones is good news for jewellery design. It encourages greater individuality and moves attention away from a narrow list of familiar choices.
A vivid spinel, tsavorite garnet or tourmaline can give a jewel an identity that would be impossible to achieve by selecting a conventional stone merely because it is better known. The most successful choice will combine beautiful colour with suitable durability, honest disclosure and a design that protects and complements the gem.
Scarcity is helping to focus attention on these stones, but scarcity alone is not what makes them compelling. Their real attraction lies in the remarkable range of colours and natural characteristics that the gemstone world has always contained.