What Are Diamonds

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Page 1: What Are Diamonds
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What Are DiamondsIn mineralogy, diamond(from the ancient Greek

adámas "unbreakable“ ) is an allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice . Diamond is less stable than graphite, but the conversion rate from diamond to graphite is negligible at ambient conditions . Diamond is renowned as a material with superlative physical qualities , most of which originate from the strong covalent bonding between its atoms.

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In particular, diamond has the highest hardness and thermal conductivity of any bulk material. Those properties determine the major industrial application of diamond in cutting and polishing tools and the scientific applications in diamond knives and diamond anvil cells . Diamond has remarkable optical characteristics. Because of its extremely rigid lattice, it can be contaminated by very few types of impurities, such as boron and nitrogen. Combined with wide transparency, this results in the clear, colorless appearance of most natural diamonds. Small amounts of defects or impurities (about one per million of lattice atoms) color diamond blue (boron),yellow (nitrogen),brown(lattice defects), green(radiation exposure),purple, pink,orange or red.

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How Is CHEMISTRY Involved In Diamond

• The chemical formula of diamond is C which is the chemical symbol for the element carbon. Soot and graphite are also made up of carbon atoms and have the same chemical symbol, C. So what's the difference between soot, graphite and diamond if they are all made up of the same carbon atoms?

• Carbon atoms can be arranged in many different physical forms called allotropes.

• An allotrope is a form of an element that has different physical properties ( eg . Colour , crystal shape, hardness, melting points,  boiling points, etc.) due to different arrangements of atoms or molecules within the structure.

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• Four allotropes of carbon are diamond, buckminsterfullerene (bucky balls), graphite and soot. Since all are forms of the element carbon, they each have the same chemical symbol C.

• The allotropes of carbon however, differ greatly in their structure and properties.

• In diamond the carbon atoms are covalently bonded to one another producing a three dimensional network solid. Each carbon atom is bonded to four other atoms throughout the crystal lattice.

• Diamond has no free electrons because they are all involved in bonding and is therefore a poor conductor of electricity.

• Diamond is the hardest substance known and is used to cut glass and in industrial drill bits. Diamond is widely sought after because of its rarity and unique cystalline structure and is used in jewellery.

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Manufacturing Of Diamond A great deal of planning, patience,

wisdom and experience goes into transforming the world's hardest material into the beautiful diamonds. Diamond cutting is the art, skill and, increasingly, science of changing a diamond from a rough stone into a faceted gem. Diamond cutting requires specialized knowledge, tools, equipment, and techniques because of its extreme hardness .

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Processes Required For Manufacturing Planning: There are many details that must be considered when planning to cut

the diamond, such as, size, shape, cleavage planes and inclusions. The goal of the diamond cutter is to have the most carat weight possible at the lowest production cost, while having the best cut. Scanning devices are used to get 3-dimensional computer models of the rough stone. Also, inclusions are photographed and placed on the 3D model, which is then used to find an optimal way to cut the stone. If the diamond is incorrectly marked by even a fraction of a millimeter, the result can be a difference of thousands of dollars!

Cleaving: Cleaving refers to splitting a stone along its grain by striking it. A

rough stone is cleaved if there are conspicuous defects and/or inclusions which would prevent it from being made into a single gemstone. Cleavage is the tendency of crystalline materials to split along definite planes. Due to its atomic structure, a diamond can be cleaved in four directions parallel to each of the four octahedron crystal faces. Cleaving is a critical step as a mistake by the "cleaver" could shatter the stone.

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Sawing: A stone-cutting saw is a thin disk made of phosphor

bronze. As the saw blade rotates it continues to pick up or "recharge" itself with diamond dust which is the cutting agent. It can take several hours for the saw blade to cut through a 1ct rough diamond.

Bruting: Bruting is the process whereby two diamonds are set

onto spinning axles turning in opposite directions, which are then set to grind against each other to shape each diamond into a round shape. This can also be known as girdling. The bruting process is only necessary for round brilliant diamonds; fancy cut stones need a different preparation.

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Polishing:Polishing is the final stage of the cutting process, giving the diamond its finished proportions. The first and perhaps most crucial polishing stage is blocking. This step lays the foundation for the potential of the diamond's performance because it establishes the diamond's basic symmetry. During the blocking stage, the first 17 or 18 facets are made, creating a single cut. For some very small diamonds, the process stops here. Larger diamonds go on to the brillianteering stage. In this process a specialist called a brillianteer, polishes the final facets. It is this stage that will determine how much brilliance and fire a diamond displays. Minor inconsistencies in symmetry and proportions can make the difference between a gorgeous diamond and a dull, lifeless stone. The Hearts and Arrows in our beautiful diamonds are the result of a skilled and mastered brillianteer.

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World’s Largest Diamond Mine

This diamond mine in eastern Siberia (Mirny, to be exact) is so deep that the surrounding "air zone... is closed for helicopters" after "a few accidents when they were 'sucked in' by downward air flow..." 

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THE ENDMade by:Saachi Rai Sadh Kasturi Chowksi Mitwa Lokhandwala Romil Lakhani Manan Jariwala Aman Aggarwal