Classically beautiful, undeniably eye-catching, and the subject of a gazillion songs and pop culture references, diamonds have always been a reliable choice when it comes to jewellery. Recent years, however, have seen jewellers expanding their repertoires to include unconventional coloured gemstones, many of which are rare and equally — if not more — captivating.

These go beyond the usual suspects of sapphires, rubies and emeralds. We’re talking watermelon tourmaline (which actually does resemble the fruit it’s named after), exuberantly green chrysoprase (cherished by centuries of royals), and deep blue lapis lazuli — desired by some of the world’s greatest artists. Citrine has risen in prominence too, with reputed brands like Bulgari and Givenchy embracing it in their latest designs.

Here are 6 unusual gemstones that have caught our eye, and taken our jewellery collections to greater (and glitzier) heights.

Pink opal

The mention of opal usually calls to mind its iridescent white or blue varieties, which are known as precious opals. Those that don’t carry this same kaleidoscopic quality are named common opals. Despite this less than glamorous categorisation, pink opal — which is a form of common opal — is far from ordinary. The lovely pink stone derives its pastel pink hue from palygorskite, a mineral in the clay surrounding it, and can be slightly translucent or opaque. It’s typically sourced from Peru and Western Australia.

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Pink opal in its rough form. (Photo: Mindat/ Hudson Institute of Minerology)

Not much is known about the specific origins of pink opal, but opals in general have been associated with kings, philosophers and gods throughout history. In Greek mythology, it’s believed that Zeus, the god of thunder, wept tears that transformed into opals, after emerging victorious in battle against the Titans. During the Middle Ages, opal was thought to have healing properties, and was used in lithotherapy — where ailments were treated with gemstones.

Fast forward to present day, and pink opal is favoured by jewellers such as Chaumet, which recently incorporated the lustrous stone in the Trésors d’Afrique brooch. The whimsical bauble features an elephant head carved out from pink opal, embellished with sapphire eyes, and adorned with a trunk curled around a bouquet of flowers made from tanzanites and “mint” tourmalines.

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Pink opal is carved into an elephant’s head in Chaumet’s Trésors d’Afrique brooch. (Photo: Chaumet)

Chrysoprase

A type of chalcedony (which is part of the quartz family), chrysoprase is known for its bright green colour. Its signature hue is the result of trace amounts of nickel present within its structure.

The gemstone’s name translates to “golden leek” in Greek, and it was used by ancient Greeks and Romans to make jewellery, decorative items, and protective talismans. According to folklore, it was beloved by Alexander the Great, who wore a chrysoprase stone on his belt whenever he went to battle. Frederick II, King of Prussia also adored chrysoprase, and even had a collection of bejewelled snuffboxes constructed from it.

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It is believed that this chrysoprase snuffbox bedazzled with gold and diamonds once belonged to Frederick II of Prussia. (Photo: The Rosalinde and Arthur Gilbert Collection on loan to the Victoria and Albert Museum, London)

Today, the coveted gemstone is commonly sourced from places such as Western Australia, Tanzania, Russia and South Africa. Jewellers such as Van Cleef & Arpels and Cartier have used it to create exquisite designs worthy of royal approval.

A stunning example is the Cactus de Cartier bracelet, which is fashioned in yellow gold and covered all over with chrysoprases. Emeralds, diamonds and carnelians —  crafted to form flower-shaped motifs — are also thrown into the mix.

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The Cactus de Cartier bracelet is a dizzying assortment of chrysoprases, emeralds, carnelians and diamonds. (Photo: Cartier)

Watermelon tourmaline

Like the fruit it’s named after, watermelon tourmaline is red or pink in the middle, with a ring of green surrounding it. It is a bi-coloured variety of tourmaline, a mineral that forms within pegmatites (a type of igneous rock, which is created due to the solidification of magma) or metamorphic rocks.

Tourmalines exist in many different colours such as red, green, yellow and blue. According to an ancient Egyptian legend, the stone comes in this spectrum of hues because it passed through the rainbow. Romantic as this sounds, the tourmaline actually gets its colour depending on its chemical composition. Manganese, for instance, helps produce shades of pink and red, while lithium contributes green hues — a combination of these result in watermelon tourmaline’s colours.

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A closer look at a watermelon tourmaline (Photo: Getty)

Watermelon tourmalines can be found in Brazil, Madagascar, Afghanistan and the US. They are typically cut into slices so their prized “watermelon” cross-section is kept intact.

These rare gemstones have made for some showstopping jewels. Case in point: Cartier’s spectacular pink gold bracelet from its high jewellery repertoire, which comes mounted with a juicy 84.10-carat cushion-shaped watermelon tourmaline and sapphires. Even fine jewellers like London-based company Ntinga have jumped on the fruity bandwagon — the latter recently rolled out a series of rings and pendants festooned with watermelon tourmalines and fringed with diamonds.

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London-based fine jeweller Ntinga has released a collection of rings and necklaces featuring watermelon tourmalines. (Photo: Ntinga)

Lapis Lazuli

With its royal blue hue and versatility, lapis lazuli — a metamorphic rock comprised of calcite, pyrite and lazurite — has remained popular through the ages. Historians estimate it to have been produced for more than 6,000 years at the Sar-e-Sang mine in Badakhshan Province, Afghanistan. The stone was crafted into amulets by ancient Greeks and Egyptians, and was even mounted on pharaoh Tutankhamun’s gold funerary mask.

During the Renaissance, European artists began using ultramarine, a pigment obtained from grinding lapis lazuli, in their works. It was particularly expensive due to its rarity and the difficulty in procuring it, but prominent painters such as Johannes Vermeer and Leonardo da Vinci splurged on it anyway. Vermeer’s seminal work, Girl With A Pearl Earring, features the rich blue pigment in the character’s headscarf; while da Vinci’s Salvator Mundi (which sold for an eye-watering S$610 million last year) depicts Christ in a blue tunic coloured with ultramarine.

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King Tutankhamun’s funerary mask embellished with lapis lazuli. (Photo: Getty)

Majority of the world’s lapis lazuli still comes from northeastern Afghanistan today, but the stone has also been found in Chile and Russia. It continues to be widely used by jewellery makers, with notable brands such as Dior and Piaget incorporating it into their latest creations. Dior’s Rose des Vents line, for instance, has a yellow gold bracelet festooned with lapis lazuli, while Piaget’s Sunlight Escape range offers a dazzling diamond-encrusted watch with a lapis lazuli dial.

Over at Van Cleef & Arpels, the Bouton d’or fine jewellery collection features a necklace, pendant, bracelet and earrings that pair the elegant blue stone with yellow gold, diamonds and turquoise.

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Van Cleef & Arpels’ Bouton d’or necklace matches lapis lazuli with diamonds, turquoise and yellow gold. (Photo: Van Cleef & Arpels)

Kunzite

Discovered in California in 1902, kunzite was named after American mineralogist and former Tiffany & Co vice president George Frederick Kunz. Kunz had been presented with a batch of unknown pink crystals and managed to identify them as a  type of spodumene, a mineral that forms within rocks containing lithium.

Kunzite comes in hues ranging from pink to light purple — created by traces of manganese — and is sensitive to light. It has even been nicknamed “evening stone”, as overexposure to sunlight for extended periods of time may cause its colour to fade. Another noteworthy characteristic is its pleochroism, where the stone’s colour appears to change when viewed from different angles.

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A heart-shaped kunzite exhibited at the Smithsonian National Museum of Natural History. (Photo: Chip Clark/ Smithsonian National Museum of Natural History)

The stone has a rather short history as it was only identified a century ago, but fascinating specimens of it have been unearthed. One example is a massive 880-carat, heart-shaped kunzite on display at the Smithsonian National Museum of Natural History in Washington DC. The stone was originally from Brazil and was obtained by the museum in 1964.

Jewellers have also wasted no time in designing pieces around it, with Tiffany & Co introducing kunzite brooches and necklaces as early as 1905. Last year, its Colors of Tiffany high jewellery repertoire featured an Art Deco-inspired ring bedecked with diamonds surrounding a large emerald-cut kunzite of over 16 carats.

Fine jewellery brands have been enamoured with kunzite too. JMG by Chilean designer José María Goñi, for instance, has a flamboyant Cleopatra bracelet fashioned in yellow gold and garnet beads, and ornamented with a glorious pink kunzite, sapphires, and white and champagne diamonds.

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JMG’s Cleopatra bracelet is a showstopper with its garnet beads, white and champagne diamonds, and stunning pink kunzite. (Photo: JMG)

Citrine

A form of quartz, citrine is prized for its golden yellow hue — which it derives from iron minerals within its structure. As natural citrine is rare, many of the citrine stones sold on the market are actually heat-treated amethysts. One way to differentiate between the two is to examine the colour: If the stone’s hue is concentrated at the tips and has a white base, it’s most likely an amethyst. A natural citrine, on the other hand, tends to have a smoky consistency throughout its colour.

Found in Brazil, Madagascar and Scotland, citrine has been coveted since the days of old, when it was set in jewellery, amulets and ornamental items by ancient Greeks, Egyptians and Romans. The Scottish had it mounted on sword handles, and — in the 19th century, began adding it to brooches and kilt pins. The latter trend was partly influenced by Queen Victoria’s fondness with citrine. Even present day royals have been smitten with the golden stone — at the recent Wimbledon, Duchess of Cambridge Kate Middleton was spotted wearing a dazzling citrine ring.

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Kate Middleton was recently spotted wearing a citrine ring at Wimbledon. (Photo: Karwai Tang/WireImage)

Jewellery designers have been equally besotted with citrine; turning it into lavish pendants, rings and brooches. Stephen Webster offers a simple marquise-cut citrine ring — which looks gorgeous when layered with his quirky Jitterbug stackable rings — while actress Angelina Jolie’s Style by Jolie jewellery line once featured a magnificent necklace composed of a juicy 117.11-carat citrine pendant framed by 64 smaller citrine stones. Jolie donated the ostentatious jewel to the Smithsonian in 2015. Last month, Givenchy’s Zodiac fine jewellery range introduced a Leo ring bedecked with a lion motif and topped with a natural citrine.

At Bulgari, the new Wild Pop high jewellery collection includes a vibrantly hued Pop Flower bracelet embellished with floral motifs of citrine, pink tourmaline, rubellite and amethyst, and set against a background of mother of pearl and diamonds. You’ll steal the show for sure in this dainty Andy Warhol-inspired creation.

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Bulgari’s Pop Flower bracelet showcases a delightful array of citrine, amethyst, pink tourmaline and rubellite. (Photo: Bulgari)

Sara Yap
Deputy Director, Digital Operations (Asia)
Sara Yap is the Deputy Director of Digital Operations at BurdaLuxury, and a contributing writer to Lifestyle Asia’s dining and jewellery beats. When she’s not on the lookout for exciting new restaurants or bejewelled trinkets, she’s probably buried in a riveting read, or reminiscing the good ol’ days with her favourite playlist of ’90s boyband hits.