The word "Emerald" is derived (via Old French: Esmeraude and Middle English: Emeraude), from Vulgar Latin: Esmaralda/Esmaraldus, a variant of Latin Smaragdus, which originated in Greek: σμάραγδος (smaragdos; "green gem"). Emeralds are fascinating gemstones. They have the most beautiful, most intense and most radiant green that can possibly be imagined: emerald green. Inclusions are tolerated. In top quality, fine emeralds are even more valuable than diamonds. The name emerald comes from the Greek 'smaragdos' via the Old French 'esmeralde', and really just means 'green gemstone'. Innumerable fantastic stories have grown up around this magnificent gem. The Incas and Aztecs of South America, where the best emeralds are still found today, regarded the emerald as a holy gemstone. However, probably the oldest known finds were once made near the Red Sea in Egypt. Having said that, these gemstone mines, already exploited by Egyptian pharaohs between 3000 and 1500 B.C. and later referred to as 'Cleopatra's Mines', had already been exhausted by the time they were rediscovered in the early 19th century.
Emerald in Different Cultures, and Emerald Lore
The Gachala Emerald is one of the largest gem emeralds in the world, at 858 carats (171.6 g). This stone was found in 1967 at La Vega de San Juan mine in Gachalá, Colombia. It is housed at the National Museum of Natural History of the Smithsonian Institution in Washington, D.C.
Emerald is regarded as the traditional birthstone for May, as well as the traditional gemstone for the astrological signs of Taurus, Gemini and sometimes Cancer.
One of the quainter anecdotes on emeralds was by the 16th-century historian Brantôme, who referred to the many impressive emeralds the Spanish under Cortez had brought back to Europe from Latin America. On one of Cortez's most notable emeralds he had the text engraved Inter Natos Mulierum non sur-rexit mayor ("Among those born of woman there hath not arisen a greater," Matthew 11:11) which referred to John the Baptist. Brantôme considered engraving such a beautiful and simple product of nature sacrilegious and considered this act the cause for Cortez's loss of an extremely precious pearl (to which he dedicated a work, A beautiful and incomparable pearl), and even for the death of King Charles IX of France, who died soon after.
India's most famous temple, the Madurai Minakshiamman temple, has its chief deity as goddess Minakshi whose idol is made of emerald, most likely carved out of a single emerald stone. Written many centuries ago, the Vedas, the holy scriptures of the Indians, say of the precious green gems and their healing properties: 'Emeralds promise good luck ...'; and 'The emerald enhances the well-being ...'. So it was no wonder that the treasure chests of Indian maharajas and maharanis contained wonderful emeralds. One of the world's largest is the so-called 'Mogul Emerald'. It dates from 1695, weighs 217.80 carats, and is some 10cm tall. One side of it is inscribed with prayer texts, and engraved on the other there are magnificent floral ornaments. This legendary emerald was auctioned by Christie's of London to an unidentified buyer for 2.2m US Dollars on September 28th 2001.
Emeralds have
been held in high esteem since ancient times. For that reason, some of the most
famous emeralds are to be seen in museums and collections. The New York Museum
of Natural History, for example, has an exhibit in which a cup made of pure
emerald which belonged to the Emperor Jehangir is shown next to the 'Patricia',
one of the largest Colombian emerald crystals, which weighs 632 carats. The
collection of the Bank of Bogota includes five valuable emerald crystals with
weights of between 220 and 1796 carats, and splendid emeralds also form part of
the Iranian National Treasury, adorning, for example, the diadem of the former
Empress Farah. The Turkish sultans also loved emeralds. In Istanbul's Topkapi
Palace there are exhibits with items of jewellery, writing-implements and
daggers, each lavishly adorned with emeralds and other gems.
The
Green of Life and Of Love
Emerald is a gemstone and a variety of the mineral beryl (Be3Al2(SiO3)6)
colored green by trace amounts of chromium and sometimes vanadium.[2] Beryl has
a hardness of 7.5–8 on the Mohs scale.[2] Most emeralds are highly included, so
their toughness (resistance to breakage) is classified as generally poor. The
green of the emerald is the colour of life and of the springtime, which comes
round again and again. But it has also, for centuries, been the colour of
beauty and of constant love. In ancient Rome, green was the colour of Venus,
the goddess of beauty and love. And today, this colour still occupies a special
position in many cultures and religions. Green, for example, is the holy colour
of Islam. Many of the states of the Arab League have green in their flags as a
symbol of the unity of their faith. Yet this colour has a high status in the
Catholic Church too, where green is regarded as the most natural and the most
elemental of the liturgical colours.
The magnificent green of the emerald is a colour which conveys harmony, love of
Nature and elemental joie de vivre. The human eye can never see enough of this
unique colour. Pliny commented that green gladdened the eye without tiring it.
Green is perceived as fresh and vivid, never as monotonous. And in view of the
fact that this colour always changes somewhat between the bright light of day
and the artificial light of a lamp, emerald green retains its lively vigour in
all its nuances. The lively luminosity of its colour makes the emerald a unique
gemstone. However, really good quality is fairly rare, with inclusions often
marring the evenness of the colour – signs of the turbulent genesis which has
characterised this gemstone. Fine inclusions, however, do not by any means
diminish the high regard in which it is held. On the contrary: even with
inclusions, an emerald in a deep, lively green still has a much higher value
than an almost flawless emerald whose colour is paler. Affectionately, and
rather poetically, the specialists call the numerous crystal inclusions, cracks
or fissures which are typical of this gemstone 'jardin'. They regard the tender
little green plants in the emerald garden as features of the identity of a gem
which has grown naturally.
So where do they come from and how is it that they exist at all? In order to
answer these questions, we need to look far, far back into the time of the
emerald's origin. Emeralds from Zimbabwe are among the oldest gemstones
anywhere in the world. They were already growing 2600 million years ago, whilst
some specimens from Pakistan, for example, are a mere 9 million years young.
From a chemical-mineralogical point of view, emeralds are beryllium-aluminium-silicates
with a good hardness of 7.5 to 8, and belong, like the light blue aquamarine,
the tender pink morganite, the golden heliodor and the pale green beryl, to the
large gemstone family of the beryls. Pure beryl is colourless. The colours do not
occur until traces of some other element are added. In the case of the emerald,
it is mainly traces of chromium and vanadium which are responsible for the
fascinating colour. Normally, these elements are concentrated in quite
different parts of the Earth's crust to beryllium, so the emerald should,
strictly speaking, perhaps not exist at all. But during intensive tectonic
processes such as orogenesis, metamorphism, emergences and erosion of the land,
these contrasting elements found each other and crystallised out to make one of
our most beautiful gemstones. The tension involved in the geological conditions
conducive to the above processes produced some minor flaws, and some major
ones. A glance through the magnifying-glass or microscope into the interior of
an emerald tells us something about the eventful genesis of this unique gem:
here we see small or large fissures; here the sparkle of a mini-crystal or a
small bubble; here shapes of all kinds. While the crystals were still growing,
some of these manifestations had the chance to 'heal', and thus the jagged
three-phase inclusions typical of Colombian emeralds were formed: cavities
filled with fluid, which often also contain a small bubble of gas and some tiny
crystals.
Logically enough, a genesis as turbulent as that of the emerald impedes the
undisturbed formation of large, flawless crystals. For this reason, it is only
seldom that a large emerald with good colour and good transparency is found.
That is why fine emeralds are so valuable. But for the very reason that the
emerald has such a stormy past, it is surely entitled to show it - that is, as
long as only a fine jardin is to be seen, and not a rank garden which spoils
both colour and transparency.
The
World of Fine Emeralds
Emeralds in antiquity have been mined in Egypt since 1500 BCE, and India, and Austria since at least the 14th century CE. Colombia is by far the world's largest producer of emeralds, constituting 50–95% of the world production, with the number depending on the year, source and grade. Emerald production in Colombia has increased drastically in the last decade, increasing by 78% from 2000 to 2010. The three main emerald mining areas in Colombia are Muzo, Coscuez, and Chivor. Zambia is the world's second biggest producer, with its Kafubu River area deposits (Kagem Mines) about 45 km (28 mi) southwest of Kitwe responsible for 20% of the world's production of gem quality stones in 2004. In the first half of 2011 the Kagem mines produced 3.74 tons of emeralds.
Emeralds are found all over the world in countries such as Afghanistan, Australia, Austria, Brazil, Bulgaria, Cambodia, Canada, China, Egypt, Ethiopia, France, Germany, India, Italy, Kazakhstan, Madagascar, Mozambique, Namibia, Nigeria, Norway, Pakistan, Russia, Somalia, South Africa, Spain, Switzerland, Tanzania, United States, Zambia, and Zimbabwe. In the US, emeralds have been found in Connecticut, Montana, Nevada, North Carolina, and South Carolina. In 1997 emeralds were discovered in the Yukon. Colombia continues to be at the top of the list in terms of the countries in which fine emeralds are found. It has about 150 known deposits, though not all of these are currently being exploited. The best known names are Muzo and Chivor, where emeralds were mined by the Incas in pre-Columbian times. In economic terms, the most important mine is at Coscuez, where some 60 faces are being worked. According to estimates, approximately three quarters of Colombia's emerald production now comes from the Coscuez Mine. Colombian emeralds differ from emeralds from other deposits in that they have an especially fine, shining emerald green unimpaired by any kind of bluish tint. The colour may vary slightly from find to find. This fascinatingly beautiful colour is so highly esteemed in the international emerald trade that even obvious inclusions are regarded as acceptable. But Colombia has yet more to offer: now and then the Colombian emerald mines throw up rarities such as, the Rare 'trapiche' emeralds found in Colombia, distinguished by a six-pointed radial pattern made of ray-like spokes of dark carbon impurities. Trapiche emeralds six rays pattern emanating from the center resemble the spokes of a millwheel.
Even if many
of the best emeralds are undisputedly of Colombian origin, the 'birthplace' of
a stone is never an absolute guarantee of its immaculate quality. Fine emeralds
are also found in other countries, such as Zambia, Brazil, Zimbabwe,
Madagascar, Pakistan, India, Afghanistan and Russia. Zambia, Zimbabwe and Brazil
in particular have a good reputation for fine emeralds in the international
trade. Excellent emerald crystals in a beautiful, deep emerald green and with
good transparency come from Zambia. Their colour is mostly darker than that of
Colombian emeralds and often has a fine, slightly bluish undertone. Emeralds
which are mostly smaller, but very fine, in a vivacious, intense green come
from Zimbabwe's famous Sandawana Mine, and they often have a delicate
yellowish-green nuance. And the famous emerald mines of Colombia currently face
competition from right next door: Brazil's gemstone mine Nova Era also produces
emeralds in beautiful green tones, and if they are less attractive than those
of their famous neighbour it is only by a small margin. Brazil also supplies
rare emerald cat's eyes and extremely rare emeralds with a six-spoked star.
Thanks to the finds in Africa and Brazil, there are more emeralds on the market
now than there used to be - to the delight of emerald enthusiasts - .
A
sophisticated gemstone
Whilst its good hardness protects the emerald to a large extent from scratches,
its brittleness and its many fissures can make cutting, setting and cleaning
rather difficult. Even for a skilled gem cutter, cutting emeralds presents a
special challenge, firstly because of the high value of the raw crystals, and
secondly because of the frequent inclusions. However, this does not detract
from the cutters' love of this unique gem. Indeed, they have developed a
special cut just for this gem: the emerald cut. The clear design of this
rectangular or square cut with its bevelled corners brings out the beauty of
this valuable gemstone to the full, at the same time protecting it from
mechanical strain.
Emeralds are also cut in many other, mainly classical shapes, but if the raw
material contains a large number of inclusions, it may often be cut into a
gently rounded cabochon, or into one of the emerald beads which are so popular
in India. Today, many emeralds are enhanced with colourless oils or resins.
This is a general trade practice, but it does have the consequence that these
green treasures react very sensitively to inappropriate treatment. For example,
they cannot be cleaned in an ultrasonic bath. The substances that may have been
used by the cutter during his work, or applied subsequently, seal the fine
pores in the surface of the gem. Removing them will end up giving the stone a
matt appearance. For this reason, emerald rings should always be taken off
before the wearer puts his or her hands in water containing cleansing agent.
A
Matter Of Trust
Unfortunately, because the emerald is not only one of the most beautiful
gemstones, but also one of the most valuable, there are innumerable synthetics
and imitations. So how can you protect yourself from these 'fakes'? Well, the
best way is to buy from a specialist in whom you have confidence. Large
emeralds in particular should only be purchased with a report from a reputable
gemmological institute. Such an institute will be able, thanks to the most
modern examination techniques, to differentiate reliably between natural and
synthetic emeralds, and will inform you as to whether the stone has undergone
any treatment of the kind a purchaser has the right to know about. And one more
piece of advice on the purchase of an emerald: whilst diamonds generously
scintillate their fire in sizes below 1 carat, you should go for larger
dimensions when acquiring a coloured gemstone. True, there are some lovely
pieces of jewellery with small coloured gems to set decorative accents, but
emeralds, like other coloured gemstones, do not really begin to show that
beautiful glow below a certain size. How large 'your' emerald ends up will
depend on your personal taste, and on your budget. Really large specimens of
top quality are rare. This means that the price of a top-quality emerald may be
higher than that of a diamond of the same weight. The fascination exuded by a
fine emerald is simply unique.
Properties determining value
Cut emeralds
Emeralds, like all colored gemstones, are graded using four basic parameters–the four Cs of Connoisseurship: Color, Cut, Clarity and Carat weight. Before the 20th century, jewelers used the term water, as in "a gem of the finest water", to express the combination of two qualities: color and clarity. Normally, in the grading of colored gemstones, color is by far the most important criterion. However, in the grading of emeralds, clarity is considered a close second. Both are necessary conditions. A fine emerald must possess not only a pure verdant green hue as described below, but also a high degree of transparency to be considered a top gem.
In the 1960s, the American jewelry industry changed the definition of "emerald" to include the green vanadium-bearing beryl as emerald. As a result, vanadium emeralds purchased as emeralds in the United States are not recognized as such in the UK and Europe. In America, the distinction between traditional emeralds and the new vanadium kind is often reflected in the use of terms such as "Colombian Emerald".
Color
In gemology, color is divided into three components: hue, saturation and tone. Emeralds occur in hues ranging from yellow-green to blue-green, with the primary hue necessarily being green. Yellow and blue are the normal secondary hues found in emeralds. Emeralds are green by definition (the name is derived from the Ancient Greek word smaragdos, meaning green). Emeralds are the green variety of beryl, a mineral which comes in many other colors that are sometimes also used as gems, such as blue aquamarine, yellow heliodor, pink morganite, red beryl or bixbite, not to be confused with bixbyite, and colorless goshenite. Only gems that are medium to dark in tone are considered emerald; light-toned gems are known instead by the species name green beryl. The finest emerald are approximately 75% tone on a scale where 0% tone would be colorless and 100% would be opaque black. In addition, a fine stone should be well saturated; the hue of an emerald should be bright (vivid). Gray is the normal saturation modifier or mask found in emerald; a grayish-green hue is a dull green hue.
Clarity
Emerald tends to have numerous inclusions and surface breaking fissures. Unlike diamond, where the loupe standard, i.e. 10× magnification, is used to grade clarity, emerald is graded by eye. Thus, if an emerald has no visible inclusions to the eye (assuming normal visual acuity) it is considered flawless. Stones that lack surface breaking fissures are extremely rare and therefore almost all emeralds are treated ("oiled", see below) to enhance the apparent clarity. The inclusions and fissures within an emerald are sometime described as "Jardin" (French for 'garden'), because of their mossy appearance. These imperfections within the stone are unique to each emerald and can be used to identify a particular stone. Eye-clean stones of a vivid primary green hue (as described above) with no more than 15% of any secondary hue or combination (either blue or yellow) of a medium-dark tone command the highest prices. This relative crystal non-uniformity makes emeralds more likely than other gemstones to be cut into cabochons, rather than faceted shapes. Faceted Emeralds are most commonly given the Oval cut, or the signature Emerald cut, a rectangular cut with facets around the top edge.
Treatments
Most emeralds are oiled as part of the post-lapidary process, in order to fill in surface-reaching cracks, improving their clarity and stability. Cedar oil, having a similar refractive index, is often used in this generally accepted practice. Other liquids, including synthetic oils and polymers with refractive indexes close to that of emerald such as Opticon, are also used. These treatments are typically applied in a vacuum chamber under mild heat, to open the pores of the stone and allow the fracture-filling agent to be absorbed more effectively.The U.S. Federal Trade Commission requires the disclosure of this treatment when an oil treated emerald is sold. The use of oil is traditional and largely accepted by the gem trade, although oil treated emeralds are worth much less than un-treated emeralds of similar quality. Other treatments, for example the use of green-tinted oil, are not acceptable in the trade. Gems are graded on a four-step scale; none, minor, moderate and highly enhanced. Note that these categories reflect levels of enhancement, not clarity. A gem graded none on the enhancement scale may still exhibit visible inclusions. Laboratories tend to apply these criteria differently. Some gem labs consider the mere presence of oil or polymers to constitute enhancement. Others may ignore traces of oil if the presence of the material does not materially improve the look of the gemstone.
Given that the vast majority of all emeralds are treated as described above, and the fact that two stones that appear visually similar may actually be quite far apart in treatment level and therefore in value, a consumer considering a purchase of an expensive emerald is well advised to insist upon a treatment report from a reputable gemological laboratory. All other factors being equal, a high quality emerald with moderate enhancement should cost much less than an identical stone graded none.