<ul><li>Diamond derives its name from the ancient Greek (adamas) which means as "invincible", "untamed", "to overpower, to tame“. </li></ul><ul><li>A diamond is the hardest substance known to humankind, and is made of a crystallized CARBON that has unique powers of light reflection. </li></ul><ul><li>Since diamonds are composed of a single element, they are the purest of all gemstones. </li></ul><ul><li>Diamonds dazzle and delight - the eternal sparkling symbol of love and eternity. </li></ul>Introduction <ul><li>In mineralogy , diamond is the allotrope of carbon where the carbon atoms are arranged in an isometric-hex octahedral crystal lattice. </li></ul>
Diamonds that are mined today 1 billion to 3.3 billion years old. Highly pressurized C arbon formed this seductive and valuable mineral in the earth at depths over 150 kilometers and at temperatures greater than 10,000 degrees Celsius.. In dramatic geological events within the earth's core, melting fluids far underneath the Earth’s surface were pushed violently to the surface, causing volcanic eruptions. These explosions created conical pipes filled with kimberlite, or hardened volcanic rock. Once the original volcanic cone was removed by gradual erosion, the kimberlite pipes containing diamond is exposed. D iamonds are in fact only accidental fragments brought to the surface of the earth hidden within this kimberlite rock DIAMOND FORMATION
<ul><li>India led the world in diamond production from the time of their discovery in approximately the 9th century BCE to the mid-18th century AD. </li></ul><ul><li>Diamond production of primary deposits only started in the 1870s after the discovery of the diamond fields in South Africa; which now constitutes of 49% of world diamonds origination. </li></ul><ul><li>Top Diamond mining countries are also located in Botswana, Namibia, Canada, Zimbabwe, Angola, and Russia. </li></ul><ul><li>In 2005, Russia produced almost one-fifth of the global diamond output, reports the British Geological Survey. Australia boasts the richest diamondiferous pipe with production reaching peak levels of 42 metric tons per year in the 1990s. </li></ul><ul><li>Diamond prospectors continue to search the globe for diamond-bearing kimberlite and lamproite pipes. </li></ul>MINING INDUSTRY
<ul><li>Diamond industry can be broadly separated into two basically distinct categories: </li></ul><ul><ul><li>Gem-grade diamonds </li></ul></ul><ul><ul><ul><li>92% of diamond pieces cut in 2003 were in Surat, Gujarat, India. </li></ul></ul></ul><ul><ul><ul><li>Other important centers of diamond cutting and trading are Antwerp. </li></ul></ul></ul><ul><ul><ul><li>De Beers owns or controls a significant portion of the world's rough diamond production facilities and distribution channels for gem-quality diamonds. </li></ul></ul></ul><ul><ul><li>Industrial-grade diamonds </li></ul></ul><ul><ul><ul><li>80% of mined diamonds (equal to about 100 million carats or 20,000 kg annually), unsuitable for use as gemstones are destined for industrial use. </li></ul></ul></ul><ul><ul><ul><li>Dominant industrial use of diamond is in cutting, drilling, grinding, and polishing. </li></ul></ul></ul><ul><ul><ul><li>Also used in scientific experiments. </li></ul></ul></ul>DIAMOND INDUSTRY
In order to deal effectively with R ough diamonds, one should be well educated in the identification and evaluation of the cut and polished diamonds. A good working knowledge of diamonds in their natural form, known as roughs & is very desirable. ROUGH DIAMONDS
diamonds The C C C C 4 C’s Of 4 C’s OF POLISHED DIAMOND In selecting a diamond, the rarity, value and beauty is determined by the four factors mentioned here, called as: arat larity olor ut
<ul><li>Carat weight refers only to the weight of the diamonds and not to the dimensions of a diamond. </li></ul>CARAT WEIGHT C arat weight is the unit of weight measurement used for diamonds and other gemstones. 1 carat = 100 cents / 0.200gms / 200 milligram <ul><li>0.075 - 0.02cts diamonds are known as ‘STAR’ </li></ul><ul><li>0.02cts – 0.07cts diamonds are termed as ‘MELEE’ </li></ul><ul><li>0.07- 0.13cts diamonds are termed as ‘+11 -14’ </li></ul><ul><li>0.14 and above are termed as ‘Pointer’ </li></ul>
CARAT WEIGHT 0.10cts 3.05 mm 0.25cts 0.33cts 0.50cts 0.75cts 1.00cts 4.10 mm 4.50 mm 5.20 mm 5.80 mm 6.50 mm *Not in scale – a relative comparison
S ieves are used to sort the similar size of diamonds from a mix lot of sizes. The metal sieve plates has a specified mm sizes of mesh holes drilled in it through which the diamonds, may or may not, pass. The Sieve sizes starts from: 000 = 1.00 mm 00 = 1.05 mm = 0.05 cts 0 = 1.10 mm 1 = 1.15 mm 1.5 = 1.20 mm ,and goes on to---------- 20 = 4.5 mm = 0.33cts (33 pointer) DIMENSIONS
C larity is the occurrence of inclusions, small crystalline fractures or irregular crystal growth, or the lack of them inside the diamond. C larity grading is done using a binocular microscope under 10X corrected magnification. CLARITY
FLAWLESS IF / FL Very Very Slight Inclusions VVS1 , VVS2 Very Slight Inclusions VS1 , VS2 Slight Inclusions S1 , S2 Imperfect I1 , I2 , I3 CLARITY
COLOUR C olour is the amount of body colour in the diamond. The clearer a diamond, the more value able it is. Colorless “D” on the color scale is the most value able because it has the most clarity. However, when a diamond is graded as a fancy colour, the value increases due to the rarity of the diamond. C olour – sometimes refer as canary yellow diamonds.
GIA COLOUR GRADING Colourless D,E,F G, H, I, J K, L, M N, O, P, Q, R S, T, U, V, W, X, Y, Z Fancy Light, Fancy, Intense Near Colourless Faint Yellow Very Light Yellow Light Yellow Fancy Yellow
Colour Comparison It is not very much possible every time, even for an expert, to say the exact color of the diamond unless and until it is compared with other diamonds. M-O COLOR E-G COLOR Fancy Intense Yellow
Each of the diamond's facets must be placed in exact geometric relation to one another when the stone is being cut. Quality diamonds must be properly cut and not "spread", which means that the proper proportions are compromised to make the diamond weigh more. CUT <ul><li>The Cut is the factor that determines the brilliance of a diamond. A classic round brilliant cut diamond has 58 facets : </li></ul><ul><li>33 on the top </li></ul><ul><li>24 on the bottom </li></ul><ul><li>And the culet (1 point at the bottom). </li></ul>
To understand the sub-categories for well-cut diamonds, think of a pyramid with "Ideal" at the top. This narrow range is reserved for the most brilliant, rare and valuable diamonds. The "Excellent" range includes beautiful diamonds that return almost as much light. "Very Good" represents the balance between precise proportions and price considerations. Analyzing Cut CUT
Culet CULET Balance, Brilliance, Dispersion, and Scintillation PAVILLION GIRDLE CROWN Provide a Setting Edge for the gem Reflect light back up through the crown Prevent Chipping at the tip ROLE OF FACETS
F ancy shapes are less expensive than Rounds. There is one quality which can affect the cost of a Fancy Shape yet never appear on a Certificate, and that is "Shape Appeal". FANCY SHAPES S hape has an appealing look to it. The best way to judge shape appeal is to look at the stone's girdle outline without a Loupe, and decide if it's attractive You don't need to be a gemologist to know if a Heart
COST <ul><li>The combination of the 4Cs. </li></ul><ul><li>The availability of diamonds in the market. </li></ul><ul><li>The choices you make about the combinations of quality / 4 Cs, finally determines the cost to you, & to the consumer. </li></ul>To calculate the price of a diamond -- multiply the carat weight by the price/carat. For example : if a 1.25 carat diamond was priced at Rs.40,000 per/carat the diamond would be sold for Rs. 50,000. The cost of a diamond is determined by :
CZ Undoubtedly the best diamond simulant available today, Cubic Zirconia has been established as an affordable diamond substitute as well as an important fashion staple in itself. CZ really took off in the 1980's, when Swarovski & Co., a world-renowned Austrian producer of leaded crystal, began producing cubic zirconia for mass consumption. Recently, new developments in CZ production have led to a sparkling new array of CZs in every color of the rainbow. Most people, even trained gemologists, cannot tell the difference with the naked eye
Like a diamond? In appearance, cubic zirconia looks almost exactly like a good quality diamond, although there are some slight differences. FIRE and BRILLIANCE CZ has slightly less brilliance (sparkle) than diamond, while having more fire (flashes of rainbow colors). HARDNESS There are very few substances on earth harder than CZ. With a hardness rating of 8.5, CZ comes close to matching diamond's perfect 10 WEIGHT CZ is about 75% heavier than diamond. 1 carat (Real) Diamond = 1.75 carat CZ CLARITY The finest CZs are perfect in clarity. CZ
CUT The finest CZ is cut to exacting tolerances, according to the proportions demanded in fine diamond cutting. Finely cut CZs will have a polished girdle and more fire. Diamonds retain superb luster even after centuries of wear wherein CZ loses its luster very soon. However, The overall effect is so similar to diamond that trained gemologists often require special equipment to tell them apart. CZ
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