Sparkle in Surat, India

Recently, Conference and Exhibition on Gem & Jewellery Industry completed in surat. It was organized during 26-28 December 2008. It was organized by Government of Gujarat and it was a part of Vibrant Gujarat Global Investors' Summit 2009. two days conference, one cultural program and three day exhibition for business and general public was the main events held during this days. Around 70 different companies presented their products. The event got very good response from many peoples who visited their products. On the last days of event the organizers required to increase entry fee from 50 to 200 Rs. That is 400%, and then also there was much rush on last day. That indicates that there was a great interest in people about exhibition.

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Latest News about Diamond Industry in India

The global economic slowdown and recent terrorist attacks in Mumbai has hit India's diamond processing industry seriously. So many unskilled, semi-skilled or skilled laborers have been laid off so far in past few months in Surat and Mumbai, which are diamond hub for India.

Now slowly diamond units are resuming. As per recent estimate 45% to 55% of companies resumed their unit. Still most of units are running at almost half of their capacity. Manufacturers think that probably in next month they will be fully operational. But it mostly depends on Christmas selling trends. Recently there is some hike in sales of jewelry in retail. But there is no crazy buying order of diamond in India. The last DTC sight was only 22% compare to last month that also indicate that there is no interest for buying of rough diamonds. Most diamond manufacturers believe that the next year will be sluggish than previous year!!

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Diamond Sightholders

Diamond Sightholders

Sightholder is a company which is authorized to purchase diamonds in bulk from Diamond Trading Company(DTC). De bears group controls DTC. Out of many businesses that deal in diamond trading, the DTC chooses only few of companies, who regularly receive an allotment of rough diamonds called “Sight”. This allocation is granted according to variables factors such as the customer’s need for certain diamonds, his grading and market fluctuations. In this framework, sightholders visit the company’s offices in London ten times annually in order to examine the merchandise.

The criteria for get selected in DTC sightholder list is very strict. When establishing its list of sightholders, the DTC examine company’s economic strength, marketing capabilities and technical skills. Up to 2003 there were 135 sightholders worldwide, but in 2004 De Beers decided to restructure its ties with its customers and reduce their numbers. In may 2006 the DTC released list of 96 companies. In 2008, 79 companies were named sightholders by DTC London, South Africa and the company’s branches in Namibia and Botswana. This contract will remain valid until 2011, when the DTC will be entitled to reexamine and change the list as it sees fit.

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Crystal Structure of Diamonds

Crystal Structure of Diamonds

A neutral carbon atom has 6 protons and 6 electrons surrounding its nucleus. Four of the electrons in a carbon atom are valence electrons, which are electrons that are available to form bonds with other atoms. In graphite, each carbon atom bonds only 3 of its 4 valence electrons with neighboring carbons. The resulting structure of these bonds is a flat sheet of connected carbon atoms. Though individually strong, these layers are only weakly connected to one another, and the ease with which they are separated is what makes graphite so slippery.

This model shows how each carbon atom (ball) is connected to 4 other carbon atoms by strong chemical bonds (rods), creating diamond's rigid crystal structure. In diamond however, every carbon shares all 4 of its available electrons with adjacent carbon atoms, forming a tetrahedral unit. This shared electron-pair bonding forms the strongest known chemical linkage, the covalent bond, which is responsible for many of diamond's superlative properties. The repeating structural unit of diamond consists of 8 atoms which are fundamentally arranged in a cube.

The crystal structure of diamond is equivalent to a face-centred cubic (FCC) lattice, with a basis of two identical carbon atoms: one at (0, 0, 0) and the other at (1/4, 1/4, 1/4), where the coordinates are given as fractions along the cube sides. This is the same as two interpenetrating FCC lattices, offset from one another along a body diagonal by one-quarter of its length.

The conventional unit cell is cubic (see diagram), with a side length a approximately equal to 3.567 Å (0.3567 nm) at room temperature. From this we can derive a few other quantities.

The C–C bond length d is equal to 1/4 of the cubic body diagonal, so that d = (√3)a0/4 ≈ 1.54 Å. The conventional cell contains the equivalent of 8 whole C atoms. The atomic density is therefore 8/(a03) ≈ 8/((3.567×10-10 m)3) ≈ 1.76×1029 atoms/m3 (1.76×1023 atoms/cm3).

Each atom can be thought of as a sphere with a radius of 1/8 of the cubic body diagonal. The packing fraction is therefore [8×(4/3)π((√3)a0/8)3]/[a03], which simplifies to (√3)π/16 ≈ 0.34.

Using this cubic form and its highly symmetrical arrangement of atoms, diamond crystals can develop in a variety of different shapes known as "crystal habits." The octahedron, or eight-sided shape that we associate with diamonds is its most common crystal habit. But diamond crystals can also form cubes, dodecahedra, and even combinations of these shapes. All of these shapes are manifestations of the cubic crystal system to which the mineral diamond belongs. Two exceptions are the flat form called a macle, which is actually a composite crystal, and etched crystals, which have rounded surfaces and, sometimes, elongated shapes

Diamond is carbon in its most concentrated form. Except for trace impurities like boron and nitrogen, diamond is composed solely of carbon, the chemical element that is fundamental to all life.

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