Fancy Tanzanite by Gilay Shamika

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GUIDE HAND BOOK ON COMMON AND FANCY GEMSTONES Eng. Gilay Charles Kilayi Shamika Senior Professional Engineer & Gemologist, Tanzania Minerals Audit Agency-TMAA ©Shamika/R&D/2014/JAN /Series NO.014

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Tanzanite appear mostly as blue but it also appear as khakis,brown and pick

Transcript of Fancy Tanzanite by Gilay Shamika

  • GUIDE HAND BOOK ON

    COMMON AND FANCY GEMSTONES

    Eng. Gilay Charles Kilayi Shamika

    Senior Professional Engineer & Gemologist, Tanzania Minerals Audit Agency-TMAA

    Shamika/R&D/2014/JAN /Series NO.014

  • 1.0 INTRODUCTION

    The intention of the Guide Hand Book on Common and Fancy Gemstones is to help to

    clear confusion of colored stones synonymous terms; fancy color and multicolor ranges

    of certain colored stones. Once you miss the point of these terms, you miss the quality of

    those gems and ultimately you miss the real value for money.

    We all know fancy diamonds assume higher price than common diamonds

    (colorless/white diamonds). Does this apply to all colored stones as well? That all fancy

    colored stones assume higher prices than their corresponding common colored stones?

    And how gemologically you can differentiate the fancy color and multicolor range

    varieties of a certain colored/gemstones. Sapphire is blue but when occurs in other color,

    it is called fancy sapphire. For instance Songea Orange sapphire this is fancy sapphire.

    Tourmaline has all rainbow colors but in most cases it appears as green. Do those other

    multicolor ranges of tourmaline which are not green called fancy tourmaline? The answer

    is NO. This is the basis of confusion and the purpose of this guide book to clear that

    knowledge gap.

    Similarly, in the market, most businesspersons and valuation officials get confusion

    sometime on differentiating fancy color and multicolor ranges to establish price. The

    second confusion is all about the reference taken from diamonds where fancy diamonds

    assume higher price compared to common diamonds (white/colorless) and use that

    reference to refer to all colored stones: that all fancy colored stones must have higher

    price as well than their corresponding common colored stones. This is generally wrong

    but selectively right-because some of fancy colored stone assume higher price but some

    not. Therefore generalizing is not right.

    This guide hand book addresses the above complexity to drive the point on board and get

    rid of those knowledge gaps. Because once you miss the point of fancy color, you miss the

    value. Similarly, if you term the multicolor ranges as a fancy color and apply higher price,

    once you are in the market for sell you will get lose as well because you will definitely be

    told is not fancy is multicolor ranges with less value than that you bought before.

  • 2.0 COMMON DIAMONDS AND GEMSTONES

    A common diamonds and gemstones/colored stone means all diamonds and gemstones

    with common or known colors. The common color for diamonds is colorless or white. For

    gemstones referring to the Big Three Gemstones, common ones are; Ruby in Red color,

    Sapphire in Blue color and Emerald in Green color. Each colored stone has its own master

    color. When those gemstones/colored stones occur in their master colors, they are called

    common colored stones. But when they occur in different color, it can be fancy color or

    multicolor ranges.

    2.1 Ancient Gemstones Groups

    In ancient era the gemstones were categorized into four groups only. The central topic for

    these groups was based on the hardness and popularity of those referred colored stones.

    The hardness and popularity/favorites of Diamonds, Ruby, Sapphire and Emeralds

    derived the earlier Gemologists to group and classify other gemstones in relation to these

    gems.

    Recently Diamonds were excluded from other colored stones and its Gemological courses

    have been separated from colored stones as a full course of its own. The four groups were;

    1. White Gemstones: All white colored stones were believed to be diamonds. Therefore

    all stones with colorless or white color and tints were termed as Diamonds.

    2. Red Gemstones: All red colored stones were grouped as Ruby since ruby occurs as

    red.

    3. Blue Gemstones: Sapphire appears as a blue stone and other stones with blue color

    were all called sapphire as well.

    4. Green Gemstones: Green colored stones in ancient era were all called emerald

    referring to the color of Emerald.

  • 2.2 FANCY DIAMONDS AND FANCY COLORED STONES

    Fancy in common English language it means imagine, think, visualize or believe.

    Something so immaculate that you dont imagine, think or believe can exist or be perfect

    as it is before you.

    The meaning is the same for diamond and other Gemstones that Fancy Diamond or

    Fancy Colored stone is the one which occur with an imaginable/different color than the

    one known color that is not expected or not common/familiar for the diamond or

    colored stone to appear.

    2.3 Fancy Diamonds

    The common color for diamond is colorless or white. Many people know that diamonds

    appear with colorless or white color. When diamond appears in that color

    (colorless/white) is only called diamond.

    After years of research and development of technology for diamonds and gemstones

    identification, it came to be known that diamonds occur in other color than white or

    colorless.

    These diamonds which appear in different or unimaginable color other than white or

    colorless are known as fancy diamonds. The diamonds with color of pink, blue, green,

    black, yellow etc are called fancy diamonds. It is naturally expected diamonds to be white

    or colorless and more than 98 per cent occur in that color. Other occurrences (fancy

    colors) are only 2 per cent.

    Due to this scarcity, the fancy diamonds assume high price compared to common or

    normal white diamonds which are available in the market in abundance. Pink diamonds

    leading with premium price than the rest fancy diamonds if all 4Cs remain the same.

    In a broad note, fancy color for the diamonds is the advantage. When the miner grabs

    fancy diamond it means he/she has scored a bingo.

  • 2.4 Fancy Colored Stones/Gemstones

    Each color stone has its own master color; the common color which is mostly known for

    that gemstone to appear.

    Ruby as red, Sapphire as blue and Tanzanite as blue as well. These are master colors of

    these gemstones. When they occur into other different colors, they are called fancy.

    Fancy Sapphire: This is the colored stone with master/common color of blue. When it

    occurs into different color other than blue, it is called fancy sapphire like Pink Sapphire,

    Orange Sapphire from Songea Tanzania, and Yellow Sapphire from Madascar etc.

    In this case also, fancy sapphires assume high price due to rarity and high demand.

    2.5 UNIQUENESS OF FANCY TANZANITE

    Tanzanite Name History: Since Tanzanite is only found in one source in the world,

    Tanzania East Africa. Tiffany & Co the main distributor by then decided to name it by

    referring to the country of origin.

    Colour Ranges: Tanzanite crystal occurs as a transparent rough with different colours

    including brown, blue, greenish-blue and khaki. But the most common is the one with

    blue colour. Predominantly blue tanzanite is generally worth more than other hues. The

    deep blue (A- grade) is obtained by heating tanzanite in controlled temperature but also

    they occur naturally.

    Varieties: Tanzanite comes from Zoisite group. Before discovery of Tanzanite the only

    Zoisite varieties known were Thulite and Anyolite.

    A great deal of Tanzanite marketing makes a big deal of the "red flash" phenomenon of

    Tanzanite. This is one of the features of the stone and is due to Tanzanite's trichroism.

    Tanzanite is extremely light sensitive, with incandescent lighting (yellow lighting found

    in common light bulbs) tending to shift its color to the violet side causing the red and

    pink flashes to appear within the stone. The images below of the same stone show it

    under white (daylight) and under incandescent light respectively:

  • TANZANITE GEM IDENTITIES

    Refractive Index (RI): DR 1.69 to 1.70

    Specific gravity (SG): 3.35

    Inclusions: Often inclusion free but can include fine needles, pinpoints and clouds.

    Hardness: 6.5 to 7

    2.6 TWO TYPES OF FANCY TANZANITE

    Type One:-Faded blue/brown color: In light of the above, tanzanite occurs in two

    colors: blue and brown, but predominantly deep blue. Unlike other colored stones where

    fancy color means different color apart from the master/common color, for tanzanite the

    fancy color is the faded common color; pale blue or pale brown color. Beyond the Blue

    Light color, the Tanzanite is called fancy tanzanite or sometime colored. Therefore the

    fancy tanzanite is the one which is less bluish or brownish color below Light Blue (BL).

    In that context, fancy tanzanite commands low prices than normal tanzanite. This is the

    rule of thumb of pricing method in colored stones; low color, low price. Below is the

    standard grading of tanzanite color and inclusion.

    Tanzanite grading standards

    Colour and Inclusion Abbreviation Explanation/What is seen in Gems

    A Exceptional Colour, Eye Clean

    B Rare Deep Blue/Brown ,other Colour, Eye Clean

    BSI B Colour-Slightly Included

    BI B Colour Included

    BL B Lighter Colour Grade, Eye Clean

    BLSI B Light-Slightly Included

    BLI B Light Included

    D Opaque Material(agreed to use D instead of O)

  • Type Two: Special Fancy Tanzanite: This is like other fancy color rules, that fancy are those

    colors which are not common not blue or brown.

    Since tanzanite is available at a Single source at Mirerani, everything mined or found together

    with the pockets of tanzanite in the underground, is believed to be tanzanite. In 1990s they used

    to find pink and green gems attached to tanzanite. These colored stones were called special fancy

    tanzanite by the virtue of their origin being associated with tanzanite. On this case these special

    fancy tanzanite assumed higher prices.

    Points to ponder: Generally speaking, the price of fancy in relation to common colored

    stone depends on the defined and traditional market segments and not generalizing that

    fancy should assume higher price. As we have seen in this article some yes and some not.

    3.0 FANCY COLOR VS MULTI-COLOR COLORED STONES

    There are other colored stones which have multicolor. If the colored stone appear to have

    multicolor naturally, these color ranges are not called fancy.

    Tourmaline has all rainbow colors. Each color will have its own name and not called fancy

    Tourmaline though most tourmalines occur in green color. The same applies for Zircon and

    garnets which have different color ranges and are not called fancy.

    Therefore there are should be a clear understanding between the fancy color and the multicolored

    gemstones. The multicolored gemstones have no fancy names rather; they have the real known

    names for each type of color range;

    3.1 Some of the multicolored Color stones

    Tourmaline: Tourmaline comes in a wide range of colors. It is believed to be a gem

    with widest color ranges of any gem species.

    Varieties: Tourmaline exists in six varieties categorized by their colours.

  • 1. Rubellite tourmaline 2.Indicolite tourmaline 3.Paraiba Tourmaline

    4. Chrome tourmaline 5.Parti-colored tourmalines 6.Watermelone Tourmaline

    Zircon: It has wide range of color- colorless, strong blue, green-blue, yellow, brown, orange, red, violet. The most occurrences are strong blue and green-blue with green

    color component.

  • 3.2 Some of the Uses of Multicolored Colored Stones.

    URU bracelets proudly Tanzanian Every URU piece is unique. The URU stones are exclusively sourced from Tanzanian small-scale miners throughout the country. In appreciation of the natural beauty inherent in the rough stones, the gems are used as they are found, ensuring that no two pieces are the same. The precious metal used in each URU design is hand carved, cast and polished by an URU artisan using age-old methods. Our unique threaded bracelet strap is hand woven by an URU craftsman in a time consuming process that takes up to six hours. More than 50 meters of thread in as many as six colours is used to create each piece. Dar-es-salaam, Tanzania, @ the Slipway. The Souk 1st floor.

    WELCOME ARUSHA GEMSHOW WHERE ALL AFRICAN GEMS

    ARE CONVENED

  • 4.0 REFERENCE

    1. Eng.Gilay Shamika (2013).Gemstones of Tanzania online publication.

    2. Waterman, F (2000). Gemstones of the World

    3. Eng.Gilay Shamika (2009). Gemstones processing Methods, Tanzanite Study Case