Presentation on theme: "A Diamond is a clear transparent precious gem stone made totally of Carbon atoms (Chemical Composition 'C') crystallised in a cubic (isometric) arrangement."— Presentation transcript:
A Diamond is a clear transparent precious gem stone made totally of Carbon atoms (Chemical Composition 'C') crystallised in a cubic (isometric) arrangement which has been highly compressed over millions of years. A diamond can also be described as a transparent crystal of tetrahedral shaped bonded carbon atoms. A tetrahedron is composed of four triangular faces, three of which meet at each vertex. The tetrahedral arrangement of atoms is the source of many of diamond’s properties. A crystal structure is composed of a unit cell which is a set of atoms arranged in a particular way. These are periodically repeated in three dimensions on a lattice. The spacing between unit cells is called the lattice parameters.
The diamond jewellery supply chain (known as the diamond pipeline) is the process that brings diamonds from the earth to consumers. It has several different stages: Exploration Diamonds are found in many countries around the world, but the majority (approximately 65%) are found in Africa. The main diamond producing countries are: o Angola o Australia o Botswana Exploration Mining Sorting Cutting & polishing Jewellery Manufacturing Retailing
Pink Diamonds The pink diamond is the world's most rare and valuable diamond.The Argyle mine is the world's foremost source of unrivalled intense pink diamonds, producing 95% of the world's supply. The legend of Argyle pink diamond has grown over the past ten years. At the 1989 Christie's auction in New York a 3.14 carat Argyle pink sold for $1,510,000. Privately, Argyle has sold pink diamonds for up to $1 million a carat. White Diamonds White diamonds are produced by mines all over the world in a wide variety of shapes and sizes.The white diamonds recovered from the Argyle mine are particularly brilliant and of high quality.
Champagne Diamonds Champagne diamonds are naturally coloured diamonds that are produced in a wide range of colours from light straw to rich cognac. The 4C's of colour, cut, clarity and carat weight apply to coloured diamonds just as they do to colourless diamonds except the intensity of colour, not lack of it, plays a greater part in the valuation. Argyle Diamonds created the following scale specifically for champagne diamonds. The diamonds are graded on a C1-C7 colour scale. C1 and C2 represent light champagne, C3 and C4 medium champagne, and C5 and C6 dark champagne. The fancy cognac diamond is graded C7. Pink Champagne Diamonds Attractive champagne diamonds with secondary pink colour are also available and command a higher price per carat than champagne diamonds. These stones display slight to bold flashes of pink in their fire. As pink is one of the rarest colours found in diamonds, even secondary colours demand a higher price depending on depth and strength of colour.
Yellow Diamonds Fancy yellow diamonds come in a broad range of shades ranging from light yellow to a rich canary colour. A limited quantity of fancy yellow diamonds is recovered from the Argyle mine. Blue Diamonds Fancy blue diamonds are available in a wide range of shades, from the blue of the sky to a more "steely" colour than sapphire. Limited quantities of fancy blue diamonds are recovered from the Argyle mine. Green Diamonds Fancy green diamonds are also available. Usually, penetration of the colour is not very deep and is often removed during the fashioning of the stone. A limited quantity of fancy green diamonds is recovered from the Argyle mine.
Diamond is an optically isotropiccrystal that is transparent to opaque. Owing to its strong covalent bonding, diamond is the hardest naturally occurring material known. Yet, due to important structural weaknesses, diamond's toughness is only fair to good. The precise tensile strength of diamond is unknown, however strength up to 60 GPa has been observed, and it could be as high as 90–225 GPa depending on the crystal orientation. The anisotropy of diamond hardness is carefully considered during diamond cutting. Diamond has a high refractive index (2.417) and moderate dispersion (0.044) properties which give cut diamonds their brilliance Most diamonds are electrical insulators but extremely efficient thermal conductors. The luster of a diamond is described as 'adamantine'.Reflections on a properly cut diamond's facets are undistorted, due to their flatness.
Graphite in the pencil is made of same stuff as diamonds. Termites may suggest the location where diamonds can be found. Every year 3, 5 millions tons of rocks get blasted with purpose of finding diamonds. Diamonds in fact don’t last forever, but “only” several million years before they disintegrate. Diamond resists attack by acids or bases. Arabic diamonds are said to attract iron even better than a magnet. Almost 50 % of all diamonds originate from Africa (mostly central and southern). Diamond is regarded as the hardest material on Earth and its hardness is set to 10 which is the hardest on Mohs scale of mineral hardness. However diamond is not the hardest material in general because aggregated diamond nanorods that were first synthesized in 2005 are even harder than the natural diamonds. The hardest natural diamonds in the world come from Australia. Diamond can only be scratched by other diamonds.
The 5 C’s The key to each diamond’s quality. To establish a diamond’s quality, you must examine each of the 5C’s. Carat Weight, Cut, Color, Clarity and Certification. It is the overall combination of these that determines the value and beauty of a particular diamond. Carat The larger a diamond, the more rare. A diamond’s weight is measured in carats, and there are 100 points to each carat. Therefore, a diamond that weighs 75 points would be three-quarters of a carat. Cut The better cut a diamond, the more brilliant. While nature determines a diamond’s clarity, carat weight and color, the hand of a master craftsman is necessary to release its fire, sparkle and beauty. A well cut or faceted diamond, regardless of its shape, scintillates with fire and light, offering the greatest brilliance and value.
Color The less color in a diamond the more rare. Diamonds are graded by color, starting at D and moving through the alphabet to Z, with D being the most colorless. While most diamonds appear white, virtually all display some hint of color. Clarity The purer the diamond, the more brilliant. The greater a diamond’s clarity, the more brilliant, valuable and rare it is. Virtually all natural diamonds contain indentifying characteristics, yet many are invisible to the naked eye. Under the scrutiny of a microscope, natural phenomena, called inclusions, may be seen. Certification The fifth C, the assurance of quality. Just as important as choosing the perfect diamond, is having an outside opinion of the quality of your diamond. A diamond grading report is a quality certification from an independent gem laboratory.
Group members and their contribution: Ashu Jain (7):Editing and VFX Pallavi Patwari(19):Compilation and Content Shalin Jain(32):Content and Photography Shailja Jani(31) Prabhav Desai(20) Crispy Shah(8)