Style / Jewellery

Gemstone Guide: Gems to invest in and what to buy

If you’re ever confused about the provenance of time-honoured favourites and newly popular gems, this general guide can help.

Dec 20, 2016 | By Yanni Tan

In today’s kaleidoscopic gemstone and jewellery industry, the discovery of new mines mean fine emeralds are no longer just Colombian; impeccable rubies are not only Burmese; and top-grade sapphires do not hail solely from Sri Lanka (Ceylon). A cursory glance at the fine jewellery collections by international brands would already throw up various countries of origin for one gemstone alone. Since the industry does not always adhere to the same guidelines, some terms used to describe gemstones may range from colours to localities to mineral varieties.

Apart from old versus new, there are also antique or heirloom gemstones whose origins are unknown or hark back to ancient lands whose boundaries or territories simply do not exist anymore. You’d imagine that examining large, fine gemstones put out by the world’s top maisons would clear the air up, but the fact that these jewellers only select the best specimens means it is difficult for the layman to easily differentiate gemstones of different regions or sources. Nevertheless, being armed with some basic knowledge could help us make better and wiser buying decisions, if not sound more intelligent or interesting over the dinner table.

OPALS
Louis Vuitton Acte V Genesis

Louis Vuitton Acte V Genesis necklace with an 87.92-carat Australian black opal

Opals are commonly found throughout the world, but precious and gem-quality varieties only come from very specific localities. Australian’s famous mines in the Outback produce over 90 per cent of the world’s fine opals of all colours, with Coober Pedy being the location where the world’s largest and most valuable opal was found, and Lightning Ridge being the most prestigious and frequently featured in high jewellery collections for its rare and stunning black opals.

Louis Vuitton Acte V The Escape Capri ring with an Australian black opal; Simone Jewels The Blue Capped Kingfisher with a 6.60-carat Ethiopian opal, along with mandarin, tsavorite and green garnets, chrome tourmalines, blue sapphires, diamonds, and enamel; Chopard Fluers d'Opales ring with a 20-carat black opal, along with tsavorites, sapphires, brown and white diamonds, and lazulites

Louis Vuitton Acte V The Escape Capri ring with an Australian black opal; Simone Jewels The Blue Capped Kingfisher with a 6.60-carat Ethiopian opal, along with mandarin, tsavorite and green garnets, chrome tourmalines, blue sapphires, diamonds, and enamel; Chopard Fluers d’Opales ring with a 20-carat black opal, along with tsavorites, sapphires, brown and white diamonds, and lazulites

Ethiopia had traditionally produced poor-quality opals until as recently as 2008, when a fine gem-quality deposit was found in the Wollo province. Called Welo opals, these specimens are mostly white and display very vivid play-of-colour.

Chaumet Lumières d'Eau Parure 5 earrings with two cabochon-cut Ethiopian white opals of 17.36 carats; Chaumet Lumières d'Eau Parure 5 bracelet with a cabochon-cut Ethiopian white opal of 39.05 carats

Chaumet Lumières d’Eau Parure 5 earrings with two cabochon-cut Ethiopian white opals of 17.36 carats; Chaumet Lumières d’Eau Parure 5 bracelet with a cabochon-cut Ethiopian white opal of 39.05 carats

An up-and-coming type of opal adored by jewellers is the fire opal, the best examples of which have a transparent to translucent bright, fiery orange colour. The only country where significant deposits are found is Mexico, which has been mining it from the highlands since 1835 and eventually adopted it as the national gemstone.

RUBIES
Bulgari's Muse Burmese Song necklace with 215.75 carats of Burmese rubies originally part of an antique necklace from Jaipur

Bulgari’s Muse Burmese Song necklace with 215.75 carats of Burmese rubies originally part of an antique necklace from Jaipur

Due to their extreme scarcity, sheer beauty, as well as huge demand, the finest rubies from Burma (or Myanmar) are dearer than the best sapphires and emeralds, and even diamonds. Burmese rubies also command a premium over other rubies because of their special qualities. They have a glorious legacy as royal gems that pre-date recorded history; boast a pure, intense red called Pigeon’s Blood that holds its colour under all lighting conditions; and display a super-charged fluorescence under ultraviolet light (and also sunlight) due to their high chromium content.

A 6.25-carat oval-shaped Mozambique ruby on the Cartier Étourdissant Garance ring.

A 6.25-carat oval-shaped Mozambique ruby on the Cartier Étourdissant Garance ring.

While there are many ruby mines in Burma, the prized variety hail from Mogok in Upper Burma and possess very fine silk inclusions that maximise their brilliance. Unfortunately, the old mines have been all but nearly depleted, and the new Burmese specimens produced typically do not match up to their predecessors, although the name “Burmese” would already command a premium in prices.

Apart from Burma, historic rubies came from mines in Sri Lanka, Thailand, and Cambodia that have all been exhausted.

Cartier's Palm Tree clip-brooch, which was a special order made in 1957, boasts seven extraordinary cushion-shaped Burmese rubies

Cartier’s Palm Tree clip-brooch, which was a special order made in 1957, boasts seven extraordinary cushion-shaped Burmese rubies

Since the 1960s, East Africa has been the newest source for fine rubies, with Mozambique, Madagascar, and Tanzania being the main suppliers. Because the African specimens are iron-rich, they tend to be darker in red or have a purple undertone, while some display a slightly lighter pinkish red.

Van Cleef & Arpel's Rubis Secret watch is a set with 115 Mozambique rubies weighing a total of 151.25-carats.

Van Cleef & Arpel’s Rubis Secret watch is a set with 115 Mozambique rubies weighing a total of 151.25-carats.

Since the 1980s, mines in the north of Vietnam have also produced some rubies and pink sapphires that aren’t as fine and clean as those of Mogok’s. Meanwhile, Greenland is touted to become the next big locality for high-quality rubies and pink sapphires after mining operations began last year.

EMERALDS
Louis Vuitton Acte V Metamorphosis ring with a 5.12-carat Afghan Pandjshir emerald.

Louis Vuitton Acte V Metamorphosis ring with a 5.12-carat Afghan Pandjshir emerald.

Colombia is the global leader and brand for emeralds, being responsible for the lion’s share of the precious stone’s production in the world since antiquity. Due to the prestige of heritage and legacy, Colombian emeralds still command the highest price per carat.

Bulgari Giardini Italiani High Jewelery necklace with seven Zambian emeralds of 120.61-carats and 18 rubellite beads of 45-carats among other gems.

Bulgari Giardini Italiani High Jewelery necklace with seven Zambian emeralds of 120.61-carats and 18 rubellite beads of 45-carats among other gems.

Another South American country that also produces emeralds is Brazil, which only started doling out top-grade stones in the 1980s after many decades of mining affordable mid-range specimens. Zambia, located in the landlocked southern part of the African continent, is the newest kid on the block for emeralds. It is also rich in other gemstones such as tourmalines and aquamarines, and has attained the status of the second largest producer of fine emeralds in the world in recent decades.

Van Cleef & Arpels Peau d'Ane Enchanted Forest necklace with Afghan emerald beads of 381.04-carats and Burmese centre sapphire of 24.77-carats.

Van Cleef & Arpels Peau d’Ane Enchanted Forest necklace with Afghan emerald beads of 381.04-carats and Burmese centre sapphire of 24.77-carats.

The trace elements colouring the emeralds are chromium for Colombian specimens; vanadium for Brazilian; and iron for Zambian. The green of Zambian stones tend to be more saturated than the Colombians, and could even appear bluish due to the presence of iron. However, the famous Chivor old mines also produced emeralds with a deep, blue-tinged green.

The Brazilian stones, meanwhile, typically display a slight brown or grey cast. The type of inclusions present in emeralds also varies by their origin. Colombian emeralds are likely to have more inclusions than Brazilian and Zambian emeralds.

Bulgari Giardini Italiani Hidden treasures earrings, made from four fancy-cut emeralds totalling 143.1-carats carved from a 400-carat raw Zambian emerald

Bulgari Giardini Italiani Hidden treasures earrings, made from four fancy-cut emeralds totalling 143.1-carats carved from a 400-carat raw Zambian emerald

Very recently, the remote emerald mines of Panjshir Valley in the Hindu Kush mountains of Afghanistan are coming under the spotlight as a potential source for emeralds of excellent colour and clarity, rivalling the best Colombians and Zambians.

Van Cleef & Arpels Émeraude en majesté Tailsman papillons necklace with a cushion-cut 16.52-carat Chivor Colombian old-mine emerald, along with blue sapphires, emeralds, diamonds, and cultured pearls

Van Cleef & Arpels Émeraude en majesté Tailsman papillons necklace with a cushion-cut 16.52-carat Chivor Colombian old-mine emerald, along with blue sapphires, emeralds, diamonds, and cultured pearls

Antique Russian emeralds are prized for their colour and lucidity, and were mined from the Urals in the 1800s up until the 1990s. However, they are extremely rare today due to sporadic production and eventual mine closure.

SAPPHIRES
Piaget Sunny Side of Life earrings with oval cut pink sapphire from Madagascar totalling over 7.6 carats

Piaget Sunny Side of Life earrings with oval cut pink sapphire from Madagascar totalling over 7.6 carats

While the most legendary blue sapphires originated from Kashmir, the northern Indian region has stopped production for so long that most of the existing specimens you see today are over 100 years old, and so exceedingly rare they usually take pride of place in a museum or auctions. These sapphires are where the term “cornflower blue” came from, displaying a desirable striking and vibrant hue similar to that of cornflowers. Due to a certain type of rutile inclusions, Kashmir sapphires also possess a beautiful velvety quality.

Cartier Royal Collection 29.06-carat cornflower blue Kashmir sapphire

Cartier Royal Collection 29.06-carat cornflower blue Kashmir sapphire

Next on the prestige scale are Mogok sapphires, which are also highly limited due to the depletion of the Burmese mines. They are typically darker blue and more transparent than the Kashmir stones, with the best ones displaying a deep, rich midnight blue.

Sri Lanka (Ceylon), meanwhile, is also reputable for astounding sapphires of not just blue, but every known sapphire colour. Hues for the blue sapphire range from a pale, almost cornflower blue to the highly regarded intense royal velvet blue. Among its famous stones include the largest blue star sapphire in the world, called the Star of Adam, which was found in 2013 and weighs some 1404.49 carats; as well as Princess Diana’s 12-carat blue sapphire engagement ring, which now belongs to Kate Middleton.

Bulgari Giardini Italiani High Jewelry earrings with two octogonal step-cut blue Burmese sapphires of 25.58-carats.

Bulgari Giardini Italiani High Jewelry earrings with two octogonal step-cut blue Burmese sapphires of 25.58-carats.

And in addition to other lust-worthy sapphire colours such as brilliant pinks and glowing yellows, Sri Lanka is also well known for its highly coveted Padparadscha sapphires, which are an ethereal, delicate pink-orange akin to the shade of the lotus flower.

Frequently featured by Tiffany & Co. are Montana blue sapphires, which were discovered in Montana state in 1865 by a gold miner working along the Missouri River. The blues are typically not large, and lighter in hue than the Sri Lankans and Burmese. Other colours, including orange, yellow, green, pink, and colourless, have also been found in Montana although the mining there is still small-scale.

Van Cleef & Arpels seven Seas Mer des Étoiles ring with one oval-cut Sri Lanka sapphire of 7.29-carats surrounded by round and pear-shaped sapphires, chrysoprase and diamonds.

Van Cleef & Arpels seven Seas Mer des Étoiles ring with one oval-cut Sri Lanka sapphire of 7.29-carats surrounded by round and pear-shaped sapphires, chrysoprase and diamonds.

Other countries where fine sapphires are found include Vietnam, Tanzania, Thailand, Cambodia, Madagascar, Tanzania, and Australia.

TOURMALINES
Piaget Sunny Side of Life necklace with one oval-cut Paraiba tourmaline centre stone from Mozambique, and diamonds, pink sapphires and blue tourmalines

Piaget Sunny Side of Life necklace with one oval-cut Paraiba tourmaline centre stone from Mozambique, and diamonds, pink sapphires and blue tourmalines

Of the many terms used to describe tourmalines, the colour prefix is usually the most common, since the gemstone is one of the most colourful on Earth. The shades adored by high jewellers are blue, green, and pink, but even tourmalines of the same colour are not equal.

Among blue and green tourmalines, an expensive and valuable subset is the neon greenish-blue Paraiba tourmaline, which was first discovered in the Brazilian state of Paraiba in 1989. With its lively hue, electrifying “swimming pool” effect, and limited supply, the radiant Paraiba quickly became a darling in the industry. In 2001, similar stones of outstanding quality were discovered in Nigeria and Mozambique, which led to the term Paraiba-like, or simply Paraiba, being used for these African stones.

La Nature de Chaumet Promesse de l'Aube ring with a 16.13-carat cushion-cut indicolite tourmaline, a round mandarin garnet, pink sapphires, and diamonds

La Nature de Chaumet Promesse de l’Aube ring with a 16.13-carat cushion-cut indicolite tourmaline, a round mandarin garnet, pink sapphires, and diamonds

While debate rages over the use of the name Paraiba, some dealers and jewellers use other descriptive terms. For instance, Tiffany & Co. uses the prefix Cuprian Elbaite: cuprian meaning copper bearing, which is the element that imparts the greenish-blue to the tourmaline; while elbaite is tourmaline’s specie name. An even rarer blue tourmaline is the indicolite tourmaline, an iron-bearing elbaite variety that displays a purer light to dark saturated blue; while the elusive chrome tourmaline, coloured by chromium and vanadium, possesses an intensely saturated forest green.

There is also the superstar among pink tourmalines: the rare rubellite, named for its luscious, ruby-like hue. To be worthy of the name, a pink tourmaline has to display a saturated pink or crimson tone, and must hold its colour regardless of the light source. Sometimes, when tourmalines display two or more colour zones, such as green and pink, they are called watermelon tourmalines.

Bulgari Giardini Italiani High jewelry bracelet (convertible into a necklace) with one 21.22-carat cushion-shaped rubellite, and amethyst beads and diamonds

Bulgari Giardini Italiani High jewelry bracelet (convertible into a necklace) with one 21.22-carat cushion-shaped rubellite, and amethyst beads and diamonds

In general, apart from Brazil, Nigeria, and Mozambique, tourmalines are found in Afghanistan, Pakistan, Russia, Burma, Sri Lanka, the US, Madagascar, Namibia, and Tanzania.

This article was first published in WOW.


 
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