Tourmaline Buyer's Guide
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Tourmaline, a perennial
favorite of the gem world has long been one of the most consistently popular gem
types available. Although not as glamorous as ruby, sapphire
or emerald, in reality the beauty of tourmaline and the value of certain tourmaline
types means they can be as every bit as precious.
A bright, clean gem that comes in a kaleidoscopic assortment of colors,
tourmaline's name derives from the Sri-Lankan Sinhalese language word "turmali",
meaning "mixed" - and with the exception of quartz-based gems, tourmaline must be the most diversely colored
gem type in the world. Its diversity of color also includes color zonings,
whereby concentric or attractive line patterns of two or three different
colors within one gem are frequently seen. Other diverse effects that add
beauty and value to tourmaline are phenomena such as cat's eyes and color change.
With the depth and diversity of colors and effects seen in the tourmaline family, novices to the arcane
world of gems can find the species as a whole comparatively hard to understand
compared to less diverse gem types. Beauty, color, rarity, size,
optical effects, patterns, market demands and more must all be accounted
for.
Color Is The Most Important Factor In Determining A Tourmaline's Value
As mentioned above, tourmaline occurs in every color of the
rainbow, and within these, multiple combinations of colors also occur in
single gems. Many tourmalines have been given specific names
that are used when discussing the gem. Sometimes these named varieties are
treated as a gem type within their own right. Briefly,
the most commonly attributed names to the different tourmaline colors are:
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Rubellite tourmaline |
Red tourmaline |
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Verdite tourmaline |
Green tourmaline |
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Indicolite tourmaline |
Blue tourmaline |
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Dravite tourmaline |
Brown and Cognac tourmaline |
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Achroite tourmaline |
Colorless tourmaline |
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Schorl tourmaline |
Black tourmaline |
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Paraiba tourmaline |
Bright neon blue-green
tourmaline from Paraiba, Brazil |
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Watermelon tourmaline |
Red or pink tourmaline surrounded by a green rind that resembles the
cross section of a watermelon
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Chrome tourmaline |
Bright green tourmaline
colored by chromium |
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Paraiba Tourmaline
A rare variety of neon blue-green tourmaline, Paraiba tourmaline can occur in truly astonishingly
bright neon hues and can command prices as high as many thousands of dollars
per carat! A copper content tourmaline found in a single area in Paraiba,
Brazil, it is generally found in comparatively small sizes for tourmaline.
Recent finds of copper content tourmaline in Nigeria have also produced
identical looking bright neon tourmaline.
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Rubellite
Ranging in color from hot pinks to the deep reds reminiscent of ruby, rubellite frequently exhibits more beauty
and sparkle than its far more expensive look-a-like. Many gems in the Russian Crown jewels made in
the 17th Century, originally thought to be "rubies", are in reality rubellite tourmalines. They make excellent
alternatives to rubies and offer superb value for money
by comparison.
The most popular and in demand type of tourmaline, rubellite is often found in large crystal
sizes that can easily reach up to 50 Carats in good qualities. After Paraiba tourmaline, rubellite is considered the most expensive
variety of tourmaline.
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Pink Tourmaline
Perennially a favorite, pink tourmaline ambiguously shares a color
border with rubellite and many specimens are so close
to this boundary that they are priced at a premium. For those tourmalines that remain firmly within the
color realms of pink, consumers are offered a color range from very good
value pastel pink shades to the slightly more expensive but vivacious colors
that approach the hot pink and rubellite color shades.
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Indicolite
Like all varieties of tourmaline, the blue variety known as indicolite, offers gem and jewelry connoisseurs large bright gems
at good value. Ranging from bright blue hues to bluish green colors, indicolite tourmaline is slightly rarer
than some of its differently colored brothers and sisters, and high quality
specimens are regarded as quite collectable.
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Chrome
Tourmaline
Although a green tourmaline, chrome tourmaline is placed into a different
category due to its rich colors that derive from trace elements of chromium.
Found in East Africa, chrome tourmaline has developed a small
but loyal following, due to its rarity and attractiveness.
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Green
Tourmaline
Typically inclusion-free, green tourmaline offers gem consumers everything they want in an emerald, but at a better price. With a
reasonably plentiful supply, bright colors, high clarities and big crystal
sizes, the prices of green and chrome green tourmaline are a fraction of
the cost of equivalent emeralds. Green tourmaline has been a best seller
over the recent years as consumers wise up to tourmaline's value for money
beauty.
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Yellow Tourmaline
Ranging from greenish yellows to buttery like colors to canary yellows, yellow tourmalines are less frequently
seen than many other varieties. While pleasant and attractive gems, demand for yellow tourmaline is lower,
presumably due to consumer conditioning by the markets. Recent finds of
almost neon yellow tourmaline in Malawi, Africa, have
produced stunning yellow tourmalines that if recovered in
commercial quantities could well change consumer tastes and demands.
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Water
Melon Tourmaline
Variations in color in a crystal's cross-section sometimes have a distinct
concentric triangular or hexagonal pattern where a pink core is surrounded
by a green rind. The effect is somewhat reminiscent of the green skins and
pinkish flesh of watermelons. Often they are cut into thin
slices to show this color effect to their best advantage.
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Bi
Color & Tri Color
Variations, zones and color bands in tourmaline are often purposefully accented
cutting style to show the sometimes-attractive bands and zones of color
streaking across the gem. Occurring in all colors infinitesimal
variations, they are often seen in long acicular crystals.
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Cat's
Eye Tourmalines
Cat's eyes have long been coveted for their beautiful optical effects. Glance
at a cat's eye gem and you will see a bright band of light
silently gliding across the surface. Cat's eye tourmalines occur in many colors
but a most frequently seen in rich green.
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Color
Change Tourmaline
Color change tourmalines present gem lovers with an opportunity to own a
rare and stunning alexandrite effect gem for a fraction of
the cost. As if reflecting tourmalines diversity, the color changes
occur in many different colors, not just the green to red we usually associate
with color change gems such as alexandrite or color change garnet.
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How Carat Weight Of Tourmaline Affects Per Carat Prices
Tourmaline frequently occurs in large crystal sizes and such large specimens
can be thought of as being fairly accessible. Large crystal sizes also help
to enhance tourmaline's perceived depth and richness of color.
Similar to most other gems, when the carat weight of a tourmaline increases, so does the price
per carat. However, large tourmaline crystals with their abundant
occurrence rates are simply more plentiful than in habitually smaller gems
such as ruby and sapphire. This means that weight related
price jumps in tourmaline are less severe than in ruby and sapphire. Indeed, it is not uncommon for
comparable quality 3 Carat, 4 Carat, and 6 Carat tourmalines all to have the same or very
similar per carat prices – something that is unthinkable regarding diamond, ruby and sapphire.
Freedom From Inclusions
Ideally a tourmaline should allow the free transmission
of light throughout its body without any hindrance – quite literally, the
ideal is “crystal clear”. As with all gems reality teaches us to expect a few
of nature's imperfections. However, tourmaline is an interesting position of
having varying clarity tendencies in accordance to its color.
The GIA divides all colored gems into three categories for the purposes
of clarity grading, based upon their habitual tendencies to exhibit inclusions.
In order of the least habitually included to the most habitually included,
the scale is: Type I, type II and type III. Briefly, these GIA clarity classifications
for tourmaline are:
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TYPE I |
Often virtually inclusion-free |
Green tourmaline |
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TYPE II |
Usually slightly Included |
Blue tourmaline
Orange tourmaline
Yellow tourmaline
Bi & Tri Color tourmaline |
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TYPE III |
Almost always included |
Red tourmaline
Pink tourmaline
Watermelon tourmaline |
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Shape & Cut
Faceted tourmalines (those with flat polished faces) are found in a variety
of shapes and styles. Due to the prevalent long acicular crystal shapes
of tourmaline, emerald cuts and fairly elongated emerald
cuts are commonly seen. Ovals and cushion cuts are common, as well as other
shapes such as emerald cuts and hearts shapes.
A perfectly cut tourmaline should always exhibit good symmetry
and polish conditions, facets should be aligned straight in relation to
the gem's girdle, and also to each other. Polish conditions should be good
with no visible surface pits or polishing lines.
Cabochon cuts are most commonly applied to those tourmalines whose clarity is not ideal
for faceting. However, they are also used to develop and display cat's eyes in chatoyant tourmaline. Well-cut
and proportioned cabochons with good symmetry, which are semi-transparent
with smooth un-cracked domes, are the ideal.
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Classical & Modern Sources of Tourmaline
Tourmaline is mined in Tanzania, Kenya,
Madagascar, Mozambique, Namibia, Afghanistan, Pakistan, Sri Lanka, and California
and Maine in the United States and countless other countries and locations.
Arguably the largest producers are the Minas Gerais and Bahia areas in Brazil,
where almost every color of tourmaline is found. However, the only
geographical location that imparts any kudos or value to tourmaline in the
manner that Mogok does to rubies, is Paraiba in Brazil.
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The Use Of Heat
Many tourmalines seen on the market today have
been subjected to high temperatures in an age-old practice that is said
to have originated in Sri Lanka some 2,000 years ago. They are heated at
high temperatures to improve their clarity and to intensify their colors.
However, there are also many tourmalines on the market are not heated.
Unusually, the market makes little or no distinction at all between the
heated and non-heated specimens.
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