Tuesday, December 15, 2009

GEMS


TOURMALINE



Tourmaline occurs in a wide range of colors and each variety takes a different name according to its main color.The most important are: rubellite – red; indicolite – blue; verdelite or simply tourmaline – when green prevails. Brazil is the main source of this popular and beautiful gemstone. Designers enjoy creating unique jewelry with its array of colors.
Color: all colors. Green is the most popular; red and blue are rarer.

Tone: variable. Very dark tones are less valuable.

Transparency: greens and blues usually have no visible inclusions and the red variety usually has some inclusions.




AQUAMARINE

Aquamarine is a crystalline gemstone that comes in pastel shades, hence, the darker the rarer and more valuable.

The most traditional Brazilian colored stone, the aquamarine is highly fashionable and sought after. Large faceted aquamarines are frequently seen in exquisite jewelry.
Color: blue, with a unique touch of greenish-blue overtone.

Tone: very light to dark, usually pastel blue and never too dark.

Transparency: usually shows no visible inclusion in faceted gems.







EMERALD



One of the most important colored gemstones for its universal acceptance, the emerald presents a wide range of qualities and prices, allowing limitless options for jewelry creation.

The combination of color, transparency and the visible inclusions confer every fashioned emerald a unique personality.
Color: green, varying from yellowish to bluish overtones (the choice is a matter of taste).

Tone: variable. Very light or very dark ones are less desirable.

Transparency: variable – the more transparent, the more valuable.

Translucent emeralds can also be very beautiful.

Treatment: clarity enhancement is always present.






DIAMOND

Unsurpassed by its ability to concentrate and irradiate light, diamond leads the world of gemstones as the symbol of love and eternity.

Produced in many regions of the world, including Brazil, it is present in almost all fine jewelry, either as the main stone or to complement colored gemstones.
Color: colorless to various grades of light yellows on a scale from D to Z. Fancy Colors are from another category including more intense yellows, browns, pinks, blues, black and many combinations of them.

Clarity: the purity is determined on a scale of ten categories.






AMETHYST


The oldest of gemstones used by humankind, with records dating back 25,000 years. The correct faceting of a fine amethyst crystal can provide a warm and deep reddish purple gemstone of great beauty. Beautiful and affordable, the amethyst is among the most popular gemstones.
Color: purple with bluish or reddish overtones.

Tone: light to dark. Very light or very dark are less desirable. Rich, deep reddish-purple is the finest quality.

Transparency: usually with no visible inclusions, but sometimes the unevenness of the color bands can be seen. Correct faceting is imperative.



PARAIBA TOURMALINE

About 600 million years ago, a unique geological event created the most spectacular gemstone variety of the tourmaline group – the Paraiba tourmaline. The Paraiba tourmaline was first found in Brazil in the late 80's, then in Nigeria in 2000 and later on in Mozambique, in 2004.
The unveiling of the Paraiba tourmaline, when first perceived by the human eyes, creates a strong emotional impact, due to its sparkling and vivid blue color. It is love at first sight: the gem has an inner light of its own, a neon or electrical splendorous blue that talks to the heart. It is pure emotion!
Tourmalines come in many colors, including blue (indicolite), but, due to the presence of small traces of copper and manganese, a new, unique and vivid turquoise or neon blue to blue-green color never seen before was found, which made it possible to establish a new gemological variety of this tourmaline, named "Paraiba" tourmaline by the trade.
The gemstone world was captivated from the very beginning by the beauty and spirited colors of the Paraiba tourmaline. In no time at all they achieved great popularity, and today they are among the most sought-after and most expensive gemstones in the world. Prices are expected to keep climbing, as demand is increasing in a faster pace than supply. Five-figure prices per carat are by no means exceptional for fine quality neon blue and neon blue-green gemstones over five carats.







IMPERIAL TOPAZ


The brightness and color intensity of this very rare gem were already highly recognized and cherished by Russian Czarinas three centuries ago.

A gemstone from a single source, Imperial Topaz is mined only in Brazil.

The following decades will see an even higher appreciation for this incredible gemstone.
Color: yellow, orange, peach or salmon, pink and sherry-red or reddish cognac.

Tone: light to dark, but never too dark. The darker tones and the ones closer to the reddish hue are rarer and consequently more expensive.

Transparency: highly transparent and usually with no visible inclusions.







TOPAZ


The brightness and the celestial colors of the blue variety of Topaz crowned this gemstone as the most popular and affordable in the last decade.

With the new technology of permanent and safe color enhancement, the market isnow supplied with a beautiful blue gemstone.
Color: blue. Commercial names such as sky-blue, Swiss-blue, cobalt blue are sometimes used to refer to different blue hues.

Tone: light to dark. Transparency: transparent and free of visible inclusions.

Treatment: all blue topazes in the market are color-induced by the combination of radiation and heating processes.







RUBILLITE


Rubellite is the noble red to intense pink variety of the tourmaline group.
Today, it is a great option for the super rare and extremely expensive fine large rubies.
Brazil is one of the main sources of this unique and beautiful gemstone.
Color: from red to shocking pink.
Slight purplish tones give a special touch of personality to this rare tourmaline variety.
Tone: variable. Lighter tones are just called pink tourmalines and extremely dark tones are less valuable.
Transparency: Visible inclusions are most frequent and can affect transparency and value.






TANZANITE


Discovered and mined only in Tanzania since 1967, tanzanite quickly became admired and popular for the unique combination of its vivid purplish-blue color and high transparency.
The demand will probably surpass the supply in the future.
Color: blue with overtones of purple. Tone: very light to very dark. Larger stones tend to a deeper rich color while smaller stones have lighter tones, displaying a lavender color.
Transparency: transparent – very dark colors in larger stones can reduce visual transparency.
Treatment: all tanzanites are heated to permanently display the violet-blue color.







OPAL


Perhaps the most intriguing of all gems for its capacity to display multicolored flashes of light at the same time.
When in movement, it gives the visual sensation of a living object.
Australia and Brazil are the only important sources of precious opal. Production has been irregular; consequently, the finer qualities are quite rare.
Color: white opal has a light body color. Black opal has a dark body color. The rare presence of the set of colors effect is what makes the opal precious. Set of Colors: the quality of the precious opal is determined by the quality and distribution of the multicolored flashes of light within each cabochon cut opal.
Transparency: translucent to semi-transparent.




CITRINE


Bright golden-yellow and dark brownish-red are joyful color varieties of this amethyst sister known as citrine.
Sometimes amethyst and citrine occur in the same crystal, taking the name ametrine. Brazil is the main source of both amethyst and citrine, offering a wide range of options.
Color: yellow, brownish-yellow, orange and reddish-yellow or cognac.
The most valuable color is the fine brownish-red (cognac) and is referred to as "Rio Grande".Tone: light to dark.
Very light or very dark hues are less desirable.
Transparency: like the amethyst, the proper faceting will display maximum beauty.
Treatment: almost all citrines are heated to permanently display their potential vivid colors.

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