Learn more about the precious, semi-precious, and organic stones, that emanate character in our remarkable collection.
PRECIOUS GEMS
Diamond
The hardest material known to man, diamond gets its name from the Greek ‘adamas’, meaning 'unconquerable'.
A cubic crystal form of pure carbon, diamond’s combination of hardness, characteristically bright ‘adamantine’ lustre and high dispersion or ‘fire’ have captured our imaginations for millennia.
The earliest recorded sources of diamonds were from India, found glittering at the bottom of river beds. These stones, known as ‘Golconda’ diamonds after the Indian city of Golconda where they were traded, were famed for their whiteness and purity, and some of the world’s most famous and historic examples, such as the Koh-I-Noor in the Queen Mother's Crown, can be traced to these distant origins.
By the mid 1700s, similar riverbed deposits of diamonds were being found in Brazil, but it wasn’t until the 1867 discovery of the 21.25 carat ‘Eureka’ diamond on a farm in South Africa that these rare gems were actually mined. These South African deposits revolutionised the worldwide jewellery industry and yielded some of the most important diamonds ever discovered, such as the Star of Africa, and the record-breaking 3106.75 carat Cullinan diamond, later re-cut into a number of stones in the British Crown Jewels.
Today, though no longer the sole preserve of royals and aristocrats, diamonds still enjoy their place as the most valuable and prestigious gemstone, and are the only stones with a standardised and dedicated grading system. Due to their beauty and incredible durability, diamonds make an excellent choice for any jewel, whether as a principal or accent stone.
Emerald
Alongside rubies and sapphires, emeralds complete the triumvirate of precious stones. They are also some of the most historically treasured gemstones, and emerald mining is documented as far back as 1500 BCE, supposedly on mount Smaragdus in Egypt.
Emeralds are a variety of the mineral beryl (which also includes aquamarine, morganite and heliodor), and owe their extraordinary green to chromium impurities.
The most famous sources of emeralds are found in Colombia, with the Muzo and Chivor mines producing particularly important examples. Today, Colombia is still the world's main source of gem quality emeralds, but increasingly mines in Zambia and Pakistan are producing excellent examples.
Due to their chemistry and the way they are formed, emeralds are very rarely without inclusions, and enjoy an enviable position among precious stones in having their inclusions not only accepted, but celebrated.
These various combinations of inclusions, often known as an emerald's 'jardin', can reveal the minutiae of the emerald's formation in the earth and occasionally its precise geographical origin. Due to these inclusions, emeralds are often traditionally treated with oil, which absorbs into fissures within the stone and helps to keep the stone at its most transparent.
Emerald is the birthstone of the month of may, and is associated with the star sign cancer. At 7-8 on the Moh's scale of hardness, emeralds are quite hard, but can be brittle due to their structure, meaning that protective settings are important for everyday wear.
Ruby
In terms of price per carat, a good ruby is second only to the rarest diamonds in value. Chemically identical to sapphires, rubies belong to the corundum family of minerals, but owe their distinctive shade of vivid red to chromium impurities.
Rubies are another extremely historic stone, and have been treasured for millennia, particularly in India where they were known as the 'king of gems'.
For all their prominence however, rubies of good colour and clarity in sizes over a carat are exceptionally rare, and good examples can command extremely high prices at auction.
Traditionally, rubies from Burma are the most valued, particularly those fabled stones showing a rich, pure red with the slightest hint of blue, known as 'Pigeon's Blood'.
In addition to the historical Burmese sources, rubies from Thailand, Cambodia and Vietnam are also highly regarded, as are newer sources, such as Mozambique.
Like sapphire, ruby is often heat treated to improve its colour, meaning that high quality, untreated specimens are highly sought after.
The birthstone for the warm summer month of july, the word 'ruby' comes from the latin 'ruber', meaning red, and it is this colour that has led to their association with love and romance, as well as warmth, energy and vitality.
Like all corundum, ruby is a 9 on the Moh's scale of hardness, meaning that in addition to its beauty, it is a very hard-wearing stone, perfectly suitable for everyday wear.
Sapphire
Sapphires are a form of the mineral corundum, and it is in their blue variety that they are most revered.
Formed by an intricate interplay of iron, titanium and vanadium impurities, the unrivalled blue of sapphires led them to be known as the 'Stone of Heaven', an association with holiness in the medieval era that made the stone a popular choice for ecclesiastical rings, strongly affiliated with the church.
Historically the most valuable sapphires are from a now-extinct source in Kashmir, at the border of northern India and Pakistan. These stones display a distinctively rich, velvety blue, often with a slight haze giving the stone a 'sleepy' appearance.
Sapphires from Myanmar (Burma), are also prized for their deep, pure shade of 'Royal Blue', whereas those from Sri Lanka (Ceylon), are known for their softer, slightly more violet shade of blue known as 'cornflower'.
Aside from these shades, sapphires also display a whole spectrum of attractive colours, from bright yellows and oranges through to subtle greens, deep violets and vivid pinks, and can even be completely colourless.
Among this rainbow of colours, another highly sought-after type of sapphire is ‘padparadscha’, a Sanskrit term meaning ‘lotus blossom’, which describes a peachy colour, balanced between orange and pink, reminiscent of a sunset.
To keep up with demand, the majority of commercially available sapphires have been heat treated to improve their colour, meaning that untreated sapphires of good colour and transparency are particularly rare and valuable.
A cluster ring set with a blue sapphire within a border of white diamonds is an enduring classic of jewellery design, most famously adored by Princess Diana and the Duchess of Cambridge.
SEMI-PRECIOUS GEMS
Agate
Quartz is one of the most abundant substances in the earth’s crust, but mankind has treasured it for its beauty in a variety of forms since ancient times.
Some of its forms, such as colourless rock crystal, amethyst and citrine, are single, transparent crystals of quartz. However, quartz can also grow as millions of interlocking microscopic crystals (‘cryptocrystalline’ structure), and in this state it is known as chalcedony.
Chalcedony can take a number of forms as well, but perhaps the most famous is agate. Agate is the name of any form of chalcedony that is exposed to different colouring agents during its growth and displays a banded, layered structure as a result.
Agate is therefore a beautiful and tremendously varied stone, renowned for its intricate patterning. This has been put to dramatic use for millennia, cut en cabochon or polished into beads to display their striped patterns, or ingeniously carved in cameos, with one layer carved in relief to stand out against a contrasting background.
A hard, durable and surprisingly affordable stone, agate is suitable for almost any type of jewel, and its variations in pattern ensure that no two examples are alike.
Amethyst
The deep purple of amethyst is one of the most distinctive colours of any stone, unrivalled in its richness.
This extraordinary colour is the result of a combination of iron and other metals within its crystal structure, and natural irradiation within the earth. The resulting hue has given amethyst a long-standing affiliation with wine, and was thought to protect against intoxication - in fact, its very name derives from the Ancient Greek 'amethystos', simply meaning 'not drunk'.
Elsewhere its beauty has taken on a more spiritual significance, commonly used for prayer beads in Tibet, and being used as a protective talisman in battle in medieval Europe.
Traditionally, the best amethyst was mined in Siberia, with these stones exhibiting an extremely deep, bluish purple. Up until the 18th century, amethysts rivalled sapphires, emeralds and rubies in value, but the discovery of large deposits in Brazil gradually brought this extraordinary stone to a wider audience.
As quartz, amethyst is a relatively hard stone, at 7 on the Moh's scale, and is perfectly suitable for daily wear in protective settings, and is also the birthstone for the month of February.
Aquamarine
Aquamarine is a pale blue variety of beryl, the mineral family which also includes emerald, as well as the yellow variety heliodor and the pink variety morganite. In contrast to emeralds, aquamarine is often found in relatively large, clean crystals, the most famous source being the Santa Maria mine in Brazil.
The clarity and delicate blue hue of aquamarine has given the stone the obvious affinity with water from which its name is derived.
Aquamarine is the birthstone of march, and historically the stone been endowed with talismanic properties, protecting sailors on their travels by ensuring a calm, blue ocean.
Chrysoberyl
Chrysoberyl gems are typically yellowish green stones that take their name from the Greek 'chryso', meaning 'golden', and 'beryl', meaning 'green'. Although chrysoberyl is the group term, popular varieties are Alexandrite and Cat's Eye. Alexandrite is particularly rare and valuable, and desired for the way it's colours appear differently when in artificial or natural lighting conditions.
A cat's eye chrysoberyl, or cymophane as it's also known, is a chrysoberyl that has been polished and smoothed into a cabochon form and reflects a long thin strip light across the middle of it's surface - similar to the effect of contracted cat's pupils.
Chrysoprase is a rare and valuable variety of chalcedony quartz, and is prized for its minty-green appearance, which results from a distinctive colouring agent; nickel impurities.
Chrysoprase is said to help in balancing the conscious and unconscious realms of the mind, and was revered by the Ancient Greeks, Romans and Egyptians for its many great powers and unique soft colouring.
The structure of a chrysoprase is cryptocrystalline, meaning it has a composition of minute hexagonal crystals that are so fine that they are almost unidentifiable as distinct particles under normal magnification.
Citrine
A popular variety of the quartz gem family, Citrine is very recognisable for its pale yellow colouring.
Almost identical in composition, a citrine is extremely similar to another quartz, Amethyst, with the only differing attribute is the rate of oxidisation of their iron impurities during its formation.
Due to the obvious connotations of it's hue, citrines symbolise the sun, warmth, energy and life and were particularly popular during the postwar Art Deco period in the form of large impactful stones - however has been used for decoration for thousands of years, and even mentioned in the Bible.
Garnet
The name ‘garnet’ actually encompasses an entire family of gemstones, each with different characteristics. The two best-known varieties are pyrope and almandine garnets, both of which are red - slightly orangey red in the case of pyrope, and purplish, wine red for almandine.
Both have been historically popular for their rich, saturated colour and excellent durability, and were most famously used in dramatic late 18th century Central European ‘Bohemian’ jewels, which were set exclusively with flat gut garnets in foil-backed settings.
Other varieties of garnet include the golden honey-coloured hessonite, and also spessartine or ‘mandarin’ garnets, which are a vivid orange.
Even rarer are the green varieties of garnet: demantoid, meaning ‘diamond-like’, first mined in Russia in 1868 and prized for its extraordinary fire, and the more recently discovered tsavorite, displaying a green close to that of emerald, and named after Tsavo national park in Kenya where it was first mined.
Both stones are very rare in sizes over a carat, and are highly valued as a result. Garnets in all their varieties are beautiful and often very underrated and affordable stones, showing a wide variety of rich colours, and well suited for everyday wear.
Jade
‘Jade’ is a general term used to describe two unrelated stones: nephrite and jadeite. Nephrite is one of the toughest materials known to man, composed of intricately intertwined fibrous crystals, and occurs in deep green, russet, yellow and white tones.
Though traditionally mined and extensively worked in Central America and Australasia, nephrite is perhaps most closely affiliated with China, where nephrite, or yù, was extensively used by imperial workshops for decorative carvings, censers, vases, sceptres and monumental works for the emperor’s own enjoyment.
In the 18th century another mineral, jadeite, known as fêi cuì, was discovered in what is now modern-day Myanmar, and began to be employed by Chinese artisans.
Jadeite is an entirely different mineral to nephrite, and displays a different palette of colours including white, a bright emerald-green, yellow, and a pretty violet colour known as ‘lavender’.
Jadeite has a brighter lustre than nephrite, and as its crystal structure is capable of greater translucency than nephrite, it is thus more widely used in jewellery.
The most highly prized jadeite is a translucent rich green variety, known as ‘imperial’ jadeite, several examples of which have broken world records at auction, including the famed ‘Hutton-Mdvani’ necklace made by Cartier for the Woolworths heiress Barbara Hutton, which sold at Sotheby’s for $27.44 million in 2014.
Gem-quality jadeite is usually cut en cabochon to showcase its colour and translucency, giving it a beautiful, soft glow that is quite different to the bright sparkle of faceted gemstones.
A tough and reasonably hard-wearing stone, jadeite is suitable for rings as well as other jewels, and makes an unusual alternative to more traditional western gems.
Kunzite
Kunzite is the best known variety of a mineral called spodumenethe. Varying from shades of pale powder pink, to more intense violet tones, it gets its delicate colour from trace amounts of manganese, and has a highly pleochroic - meaning kunzites seem to change colour when observed from different angles.
Owing to it's 'feminine' colour, kunzites are often termed the 'woman's stone' and claimed to provide support to young mothers by calming overactive children.
Kunzites have the ability to retain light; an effect known as phosphorescence, which gives the gem the power to glow in the dark. This luminous effect is due to slowly releasing absorbed energy in the form of light.
Lapis Lazuli
Lapis lazuli, or just lapis as it's commonly known, is one of the most sought after stones throughout history, representing royalty, wisdom and truth. A celestial blue colour, often golden flecks on its surface enhance its mystical and cosmic qualities.
The presence of lazurite, that is an essential component, causes the deep blue tones of lapis, whilst minute crystals of pyrite add a brassy yellow colouring.
Mined for over 6000 years, lapis was popular among wealthy ancient egyptians for decorative jewellery, as a base mineral for cosmetics and as form of protection against the 'evil eye', and was even used as a powder for a paint called 'ultramarine' which was a favourite of the painter Michelangelo.
Moonstone
A member of the feldspar family of minerals, moonstone is usually cut in a domed shape (‘en cabochon’) to show off its unique visual property, adularescence. Adularescence, also sometimes called schiller, is a sheen seen from certain angles that almost appears to illuminate the stone, and is caused by light interacting with the intricately layered structure in which moonstone forms.
Reminiscent of moonlight playing upon water, adularescence gives moonstones a poetic and ghostly quality quite unlike any other gemstone.
Morganite
Morganite is a salmon pink gem, first discovered in Madagascar by George Kunz in the early 20th century, who decided to name the stone after financier and gem enthusiast J.P. Morgan.
Its rosy colour is caused by traces of manganese in its composition, and this colour has made it popular choice for engagement rings - with it often being a more affordable option, and slightly more playful than traditional diamond styles.
Morganite is part of the 'beryl' family, which means it is closely related to emeralds and aquamarines, and has a hexagonal, prismatic structure.
Onyx
Striking yet sombre in appearance, many believe onyx gemstones to be exclusively black, however they are found in other variations such as white, red and brown.
Onyx gems are 'Chalcedony' stones, meaning they are layered with darker and lighter parallel bands, or a wider band of solid black. Onyx is formed from calcite, when water drips and evaporates from the ends of stalagmites and stalactites in caves.
Once the water has evaporated, what's left behind are traces of minerals and calcium carbonate which result in the intricate bands of varying colours.
Opal
Opals are extraordinary stones, their optical properties creating infinite variety - each has a pattern of bright iridescence all of its own, as unique as a fingerprint.
This iridescence is the product of light interacting with a minute network of spherical structures of silica within the opal, and the resulting flash of colour varies with the density and size of these groups of spheres.
The most commonly seen colours are blue and green, while the rarest are at the other end of the spectrum: orange and red. The patterns in which these colours appear are also varied - small flashes of colour are known as ‘pinfire’ opals, while a patchwork of broad flashes of contrasting colours are particularly prized, known as ‘harlequin’ opals.
The body colour of opal can also vary in both shade and transparency, including white, black, and a vivid orange variety known as ‘fire opal’.
The birthstone of october, opals occur in several varieties, notably across Mexico, Ethiopia and most famously Australia.
Peridot
Peridot is a gem-quality form of the mineral olivine. Peridot is known as an ‘idiochromatic’ stone, which means that its colour is not due to chemical impurities, as with stones such as sapphire and ruby (known as ‘allochromatic’), but is instead intrinsic to the stone, and caused by its fundamental chemical composition.
In the case of peridot, that colour is a distinctive, rich yellowish green caused by iron, with minor variations in tone depending on the percentage of iron in the crystal lattice.
Historically, peridot was famously sourced from the isle of St John in the Red Sea, but in the modern era, its principal source is Arizona in the US, but there are also deposits in Australia, Brazil, Myanmar and elsewhere.
Most surprisingly, gem-quality peridot has been found in rare pallasite meteorites that have fallen to earth. Peridot is a vivid and distinctive stone, with high lustre and reasonable hardness, and is also the birthstone for the month of August.
Spinel
At the centre of Queen Elizabeth II's Imperial State Crown is an alluring red stone, cut en cabochon. Known as the 'Black Prince's Ruby', it was supposedly taken by Edward of Woodstock, nicknamed 'the Black Prince' the militaristic and wayward son of Edward III, as payment for his military aid to the ruler of Granada.
It wasn’t until the mid 18th century that gemologists realised that this beautiful red stone was not a ruby, but was in fact another stone altogether: spinel.
Spinels were particularly favoured by the Mughal emperors of India, and several spinel beads inscribed with the names of these rulers who owned them exist in important collections, such as the ‘Timur ruby’, which is part of the British Crown Jewels, and the 500 carat Samaritan spinel in the collection of the Iranian Crown Jewels.
Historically, the most important deposits of spinel are in Tajikistan, but additional sources have been discovered in Vietnam and Burma.
Spinels range in colour from steely blues, through lavender, lilac and soft pinks, to a bright vivid red, rivalling that of rubies.
Due to its relative obscurity in the west, spinel is one for the connoisseur - a hard and durable stone, with a beautiful and distinctive colour palette. It’s perfect for rings, and makes an unusual and elegant alternative to more mainstream gems.
Topaz
The word ‘topaz’ is thought to originate either from the Sanskrit word ‘tapas’ meaning ‘fire’, or from the Ancient Greek name of the Isle of St John in the Red Sea, where the stone was thought to be originally mined.
Treasured since the classical era, topaz was traditionally mined in Russia and Saxony, its colour palette ranging from ‘imperial’ golden yellows to ‘sherry-coloured’ pinkish browns, as well as pink and colourless varieties.
As new sources of topaz were discovered in Brazil and further afield, new colours were added to this range, including naturally occurring pale greens and blues. In the modern era, colourless topaz is commonly artificially irradiated to make it a bright blue, but the elegant shades of antique stones, without treatment, have a beauty and value all of their own.
Topaz jewellery reached its peak in the 18th and early 19th centuries, when entire parures adorned queens and noblewomen.
The foil-backed topaz rivière necklaces of the era are still highly sought after today - most prominently worn by the likes of Vogue editor-in-chief Anna Wintour.
While high on the Moh’s scale of hardness, topaz, much like emerald and zircon, can also be quite a brittle stone, so when used in rings it is best set protectively and worn on special occasions.
Finally, its delicate tones can fade in strong light over time, so while perfectly suitable for outside wear, when stored, topaz should be kept away from bright lights.
Tourmaline
Tourmaline is a stone of tremendous variety, producing perhaps the widest spectrum of colour of all gems. Introduced into Europe in the 17th century, tourmaline is found in a number of sources, most notably in Brazil, and goes by a number of names according to its different hue, including rubellite (deep pink), dravite (a brownish green), indicolite (deep blue) and schorl (opaque black tourmaline).
Tourmaline is also famed for its striking combinations of colour zones within single crystals, the most famous being ‘watermelon’ tourmaline, where zones of both pink and green are present in the same stone.
In recent years, a striking neon blue variety of tourmaline has been discovered in Brazil and Mozambique. Named ‘Paraíba’ tourmaline after the location in Brazil where it was first mined, this hugely popular and highly valuable variety owes its incredible colour to copper impurities, adding yet another hue to the rainbow of colours that tourmaline is capable of producing.
Price-wise, most varieties of tourmaline fall below sapphires, rubies and emeralds, which means that for in addition to their rich colours and natural beauty, tourmalines also offer exceptional value for money.
At 7-7.5 on the Moh’s scale of hardness, it is also a reasonably durable stone, and able to cope with everyday wear.
Turquoise
Vibrant blue hues, with intricate veins of brown and black, also known as its matrix, turquoise has become so significant that we use it today as an every-day colour name.
The name 'Turquoise' is thought to derive from the Levantine traders that transported the stones from the eastern mediterranean to western Europe, labelled at the time as 'Turks'.
It's popularity extends back millenia, from ancient civilisations to modern day applications; for example as accents of colour to decorate landmarks such the breath-taking Taj Mahal in India.
Zircon
Zircons are natural stones, and are not to be confused with the similarly named but completely unrelated cubic zirconia, the ubiquitous synthetic diamond simulant. Zircons are fascinating and historic stones, prized for their unusually bright lustre and high dispersion, rivalling that of diamond.
Combined with an array of vivid colours including rich gold and sherry tones to deep greens and swimming pool blues, zircons make a beautiful and unusual choice for any engagement ring.
ORGANIC STONES
Coral
Unlike most other gemstones, coral is formed organically by living organisms at the bottom of the sea and is in fact the hardened skeleton that remains after the 'coral polyps' have died.
Typically used in jewellery design for its warm pinkish-orange colouring, in its natural form coral is dull and matt in texture, and is often polished to give it a glossy appearance to rival other gems.
Although very popular in red tones, coral is mostly white in nature but can also found in black - which is believed to purify toxins and remove negative energy. Hawaiian gold coral is the rarest coral and harder than other varieties.
Pearl
Natural pearls are the product of oysters, created in response to an irritant in the shell. The irritant, often nothing more than a grain of sand, it is coated over time with layer upon layer of a substance known as nacre, creating a shimmering and lustrous surface with a subtle iridescence.
Natural pearls are the birthstone for june, and extremely rare - by their very nature they can neither be farmed or mined, and each find is simply a stroke of good fortune. Consequently natural pearls have been treasured for millennia, synonymous with power and opulence, and worn by some of the most captivating and powerful women in history, including Cleopatra, Elizabeth I, Catherine de Medici and Marie Antoinette, as well as 20th century icons such as Elizabeth Taylor and Jacqueline Kennedy.
The best natural pearls show a highly lustrous and smooth surface, free from imperfections, combined with a regular and even shape. While natural pearls have adorned both women and men for generations, as organic gemstones, pearls are relatively soft, and more suited to occasional rather than everyday wear.
To keep their natural lustre intact, they are also best kept away from chemicals such as perfumes, which can affect the surface.