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Emerald
"Indeed there is no stone, the colour of
which is more delightful to the eye... there being
no green in existence of
a more intense colour
than this".
Pliny the Elder (23-79 AD), Historia
Naturalis
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Legend has it
that Cleopatra's favourite gemstones
were Emeralds
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When I was a boy, long before I knew or cared who old
man Pliny was, I thought Jim Henson's Kermit the
Frog was pretty fantastic. Having grown up on
'Sesame Street', the 'Muppet Show' was a programme we enjoyed as a family, with many
happy memories. I remember Kermit singing, 'It's
Not Easy Being Green', when he starts lamenting
about being the colour of ordinary things,
ending positively in full realisation that green
is good: it is cool, friendly, the colour of
Spring, and big important things, such as oceans
and mountains. In a way, Kermit's journey of
self realisation mirrors my experience with
Emeralds. Initially, I couldn't understand them,
their intricacies, personality or character.
Trying as I might to get into their 'ins and
outs', I was just out. After a while, I began to
see them for what they are, truly ancient and
fantastic gemstones. No wonder Mesopotamians
(modern-day Iraq) reportedly traded Emeralds
4,000 years ago. From Cleopatra to
conquistadors, the lust for its rare, beautiful
greens has made Emeralds one of the world's most
valuable gemstones. But the birthstone for May
isn't as easy to understand as other gems; so
hold my hand as we get clever with Emeralds.
Emerald is a member of the Beryl mineral family
(from the ancient Greek 'beryllos', meaning
blue-green stone), and commonly known as the
'mother of gemstones' because of its highly
regarded gem varieties. Apart from Emerald
greens, other Beryl gemstones include Aquamarine
blues, Bixbite reds, Goshenite whites
(colourless), Heliodor yellows and Morganite
pinks. Emerald is coloured by trace amounts of
chromium, vanadium and iron, with their relative
concentrations causing an extraordinarily
beautiful range of pastel to intense deep greens
with varying degrees of bluish, brownish,
greyish and yellowish tints. More on its colours
in a moment.
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Colombian
Emerald & Diamond 18K Yellow Gold
Ring
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Emerald's name is derived from the Greek 'smaragdos',
which means 'green gem', but as with Ruby and
Sapphire for reds and blues, prior to scientific
advances in the 18th century, the name was used
for any green gemstone. For example, because
Green Sapphire was sourced from the Far East it
was once known as 'Oriental Emerald'. One thing
to cover is the term 'Green Beryl'; logically
it's got to be the same as Emerald, right? Well,
not always. Some professionals and gemmological
laboratories split the two based on their
colouring agents, colour purities, hues or
tones. Confused? Me too! In her excellent book
'Ruby, Sapphire & Emerald Buying Guide', Renée
Newman states: "there is no agreed-upon
criteria in the trade for distinguishing between
Green Beryl and Emerald". She favours keeping it
simple for consumers, using 'Emerald' to refer
"to all Beryl ranging from bluish green to
yellowish green regardless of its tone, colour
purity or colouring agent". I support this
sensible approach.
Historically, Emerald was the mean green beauty
machine of the ancient world; Mesopotamians,
Egyptians, Greeks and Romans all coveted the
'greenest of green' gems. For those looking for
Emeralds in early civilisations surrounding the
Mediterranean, they'd have been best off seeing
the Egyptians, because this was the place where
Emerald's story begins.
Perhaps mined as early as 3500 BC, Egypt's
Emerald mines were located in Egypt's eastern
desert region and were rediscovered in 1816 by
Frédéric Cailliaud, a French mineralogist and
explorer. Even Greek miners braved heat,
scorpions and snakes to unearth Emeralds there
for Alexander the Great. This isn't to say there
weren't other Emerald sources; the Habachtal
region in the Austrian state of Salzburg might
have yielded a few Emeralds, and Roman earrings
featuring Emeralds from the Mingora Mine in
Pakistan's Swat Valley have been discovered.
There is also a legend that the Scythian
Emeralds mentioned by Pliny in his 'Historia
Naturalis' were actually from Russia's Urals,
but as far as supply is concerned, Egypt had a
near monopoly. Cleopatra, last Pharaoh of Egypt,
was big on Emeralds; she wore sumptuous Emerald
jewellery, decorated ornamental objects with
them, and presented dignitaries with Emeralds
carved with her likeness. While it's tempting to
think they were her favourite simply because of
their beauty, Cleopatra was shrewd, intelligent
and politically savvy. She understood the
importance of symbolism, glamour and prestige in
power and politics. Emeralds were more than just
pretty gems to the Egyptians, they were potent
patriotic symbols of national pride and she knew
this. When Cleopatra finally consolidated her
power base in 47 BC, with a little help from her
Roman boyfriend Caesar, she was quick to claim
the countries mineralogical riches as her own.
Despite being discovered some 2,000 years before
her birth, the Egyptian deposits will be forever
known as 'Cleopatra's Emerald Mines'.
Since Egyptian times, Emeralds have been linked
to fertility, immortality, rejuvenation, and
eternal spring, so it's no surprise they are the
birthstone for May. Pliny bestowed the benefits
of Emeralds to refresh and sooth strained eyes
and even today, we have 'green rooms' to relax
presenters in TV studios and 'hospital green' to
calm patients. Having looked at a gem parcel or
two in my time, there is some truth in this.
Emeralds (and other green gems) are definitely
easier on the eyes.
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Zambian
Emerald & Diamond 18K Yellow Gold
Ring |
When getting ready to choose your Emerald,
you'll need to understand four criteria and how
they impact value: purity of colour,
transparency, clarity and brilliance
(brightness). As with so many gems, colour is
king for Emerald, and the wise Goldilocks maxim
(not too dark or too light, just right) is
heading in the right direction. But all things
being equal, a slightly deeper richer bluish
green than the middle point is equally
desirable. What is critical is your 'purity
perception' of its green in different light
sources, remembering a gem should ideally look
good in all lighting conditions, and for the
marketplace, the purist green possible is the
most valuable. The tricky thing is that 'pure'
greens are the unicorn of Emerald, with
different experts differing on their
preferences. A little bit of yellow (typically
up to 15 percent) can enhance a pure green,
balancing its colour in incandescent light,
while a little bit of blue brings depth,
richness and warmth. Colour preferences are
subjective, so if you like them pastel because
of your complexion, I'm not going to argue, but
if you want to stick to the marketplace norm,
the best Emerald for you is your best perception
of green. Emeralds with too much blue, brown,
grey or yellow will be priced accordingly.
Transparency and clarity are best described as
two different, albeit related, things in
Emerald. In general, a transparent 'lively'
Emerald with a few bigger visible inclusions
will be valued higher than an Emerald whose
inclusions are so fine they create a murkiness
that negatively impact transparency. Emeralds'
inclusions and tiny fractures are termed 'jardin',
from the French for 'garden', and this is
definitely apt. As a Type III gemstone (click
here
for more), Emerald has visible inclusions
that we tolerate. In fact, you stand a better
chance of seeing a flock of pigs than an
eye-clean (no visible inclusions when the gem is
examined six inches from the naked eye) Emerald
above 1 carat. If I'm honest, this took some
time for me to get used to, but now all is
forgiven. In Emeralds, inclusions are the nature
of the beast and are a characteristic trait,
like a beauty spot, not a blemish. Why? Emeralds
grow slowly within metamorphic rocks (rocks that
have undergone a physical change due to extreme
heat or pressure), which limits their size. This
violent environment, combined with chromium and
vanadium trace elements, creates a veritable
inclusion fiesta. All things being equal,
cleaner large Emeralds are worth more simply
because of geological scarcity.
Last but not least, you need to appreciate the
unique brilliance of Emeralds. Influenced by
colour, cut and clarity, the 'brightness' of an
Emerald is often described as satiny, silky,
warm, soft, glowing, or my favourite, 'green
fire'. You won't get the brilliant snap, crackle
and pop of Paraíba Tourmaline in Emerald, but
nor should you. Emerald has an elegance all of
its own. Quality of cut is very important for
Emeralds as a skilled lapidary can locate its
inherent eye-visible inclusions in a way that
minimises their impact on beauty. In terms of
cut and shape, the famous equidistant steps of
the 'emerald cut' are designed to reduce cutting
pressure, accentuate Emerald's satiny brilliance
and, in the case of Colombian Emerald, maximise
rough yield. While this traditional cut is
synonymous with Emerald as red is to Ferraris,
because of the shape of the rough, ovals and
pears are common for Emeralds from Brazil and
Zambia. Material not suitable for faceting is
often fashioned into cabochons and beads. As
with all gems, look for a good shape and overall
appearance. Although Emerald is relatively
durable, it does have some special care
requirements (click here for more).
While Egypt's Emeralds are long gone, since the
16th century and the exploits of the infamous
conquistadors Hernando Cortés (who campaigned
against the Aztecs from 1519) and Francisco
Pizarro (who campaigned against the Incas from
1526), a Colombian pedigree has become
synonymous with Emeralds of exceptional quality.
By reputation and experience, Colombian Emerald
is the 'in demand' marketplace heavy weight of
Emeralds, but supply is scarce. To put this in
context, my gem dealing friend Tony Diniz on his
last buying trip to Colombia was only able to
source less than 30 pieces of Emerald from
thousands examined that met his quality
standard. As with all sources, there are good
and bad from Colombia, so just make sure you're
paying for the gem, not the name. Discovered in
1931, Zambia has the world's second largest
Emerald deposit and is also known for producing
fine quality. Other Emerald sources are
Afghanistan, Brazil, Pakistan, Russia (Ural
Mountains), and Zimbabwe.
Emerald's unique beauty requires a little
understanding to fully appreciate its character,
but once initiated into their secrets, you'll
agree with Kermit: "I am green and it'll do
fine, it's beautiful! And I think it's what I
want to be".
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Tsavorite Garnet
Campbell R. Bridges, the legendary
Scottish geologist who was the first person to
bring Tanzanite to the GIA (Gemmological
Institute of America) for identification,
discovered Tsavorite in 1967 in Tanzania and in
1971 in Kenya's Tsavo region. A Green Grossular
Garnet, Tsavorite is the trade name created in
1974 by Campbell and Tiffany's Henry B. Platt
(great grandson of Louis Comfort Tiffany), and
is named in honour of Kenya's Tsavo National
Park. Having had lunch with Campbell, I found
him an interesting man, relaying colourful
stories of living in a tree house to protect
himself from leopards and even placing a python
in among Tsavorite rough to prevent theft. He
actually challenged yours truly to a race up a
shaft at his Scorpion Mine, but I was unable to
travel to Kenya, so the jury's still out on that
one. While Emerald's greens are frequently
touted as being 'unparalleled in the gem
kingdom', Tsavorite is the one gem that can give
it a run for its money. Tsavorite is coloured by
trace amounts of vanadium, and occasionally
chromium, the same elements that give Emerald
its characteristic hues. In terms of colour, a
pure 'emerald-green' is considered by the
marketplace to be the finest, but as with all
gems, be guided by your preferences. The
reliable Goldilocks maxim again rings true (click here for more), with intense midpoints being favoured. Dark 'blackish' Tsavorite that loses
transparency and overly yellow specimens will be
priced accordingly. Tsavorite is available in a
wide variety of cuts, so look for a good shape
that accentuates its innate brilliance due to
its high index of refraction. In this respect,
Tsavorite has a crisp brilliance that 'snaps'
when compared to the 'satiny' brilliance of
Emeralds. While Tsavorite is classed as a Type
II gemstone (click here for more), like most
Garnets, it possesses few inclusions. While the
market norm is eye-clean (or as close to that
ideal as possible), larger gems with a few
eye-visible inclusions are forgivable due to
their scarcity; most Tsavorite is under 3
carats. Despite being heavily marketed in the
seventies by Tiffany & Co., 40 years on,
Tsavorite never did manage to usurp Emerald as
the greenest of greens. It may be cleaner, rarer
and more brilliant than Emerald, but Tsavorite
is plagued by scant availability. Only a handful
of its notoriously difficult to mine deposits in
Kenya, Tanzania, Madagascar and Zambia are
commercially viable, keeping prices high.
Exceptionally beautiful, Tsavorite's unique
properties have crowned it the 'king of
garnets', but due to little public awareness it
remains a choice gem for the clever gem buyer.
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Peridot
Peridot
(correctly pronounced 'Pair-ee-doh'),
derives its name from the Arabic 'faridat',
which means 'gem' and was called the
'gem of the sun' by the ancient
Egyptians and the 'evening emerald' by
the Romans. The 'classic' source for
this gemstone is Zeberget (St. John's
Island), which is located approximately
80 kilometres off the Egyptian coast in
the Red Sea. Due to this deposit having
a high nickel content it was visually
similar to Emerald and you guessed it,
many of Cleopatra's 'Emeralds' were
actually Peridot. Rich in legend and
lore, Peridot scores several mentions in
the bible (using its old name Chrysolite,
'golden stone') and was even a favourite
of pirates, who were said to have used
them for banishing evil spirits and
terrors of the night. Coloured by iron,
Peridot is the gem variety of the
Olivine mineral and ranges in colour
from green to yellowish-green, with its
'pure' green hues demanding the highest
prices. Peridot has an attractive
'sleepy' appearance with a shining glow,
which is why Peridot was mined at night
during antiquity, when the gem's natural
glow made it easier to spot. While it
can be eye-clean when small, as a Type
II gemstone, Peridot typically has
eye-visible inclusions, especially in
larger sizes. Although the world's
largest Peridot deposit is located in
the San Carlos Apache Reservation,
Arizona, China has recently become a key
player. But in my humble opinion, the
best of the best hails from the Nanga
Parbat region of Pakistan.
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Russian Diopside
Emerald? Not! Russian Diopside is a chromium-rich
Diopside known for its green to bluish
greens and is predominately mined in
Russia (Siberia), although deposits also
exist in China. Coloured by one of the
trace elements also responsible for the
'classic' greens of Emerald (and
sometimes Tsavorite), Russian Diopside
is also known as Chrome Diopside or
Imperial Diopside. Extremely rare, the
supply of Russian Diopside is
inconsistent. While it is usually
eye-clean, Russian Diopside is mostly
small sized, with anything over 5 carats
virtually impossible to obtain. Diopside
derives its name from the Greek 'di'
(two) and 'opsis' (appearance), in
reference to its double refractivity
(click here for more).
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