Diamond

Diamond

Introduction

In this paper, we will present a discussion on the properties of diamond and the social, economic and environmental issues tied to the diamond in general. Diamond is the cubic modification of carbon and as a naturally occurring solid; it is a mineral from the mineral class of elements. Diamond is usually octahedral crystal, often with curved and striated surfaces. Other observed forms are the tetrahedron, dodecahedron and the cube. The crystals are transparent, colorless or by impurities (e.g., nitrogen) or crystal lattice defects, green, yellow, brown and more rarely orange, blue, pink, red or gray to black in color (Adcock, 2001).

Diamond is the hardest natural substance. Its hardness is 140 times greater than that of corundum. The hardness of the diamond is, however, in several different crystal directions (anisotropy). It is possible to grind diamond with diamond. Diamond is optically isotropic with high refraction, high dispersion. It shows fluorescence and phosphorescence and is triboelectric. It has the highest thermal conductivity of all known minerals. The importance of individual diamonds is traditionally carats which indicate a unit corresponding to 0.200 grams (Adcock, 2001).

Discussion

The main distinguishing feature of the diamond is that it is the highest in hardness level among the minerals but at the same time, it is fragile. Diamond is an insulator. A diamond is very low coefficient of friction of metal in the air which is just 0.1, which is associated with the formation on the surface of the crystal thin film of adsorbed gas, which acts as a kind of lubricant. When such films are not formed, the friction coefficient increases and reaches to 0.5-0.55. The high hardness of diamond makes exceptional durability to abrasion. The diamond is also characterized as the highest (compared to other known materials), in the elastic modulus and the lowest ratio.

The age of the diamond can be identified by their inclusion. These inclusions occur simultaneously with the diamond that surrounds them, and often consist of silicate minerals of interest. The age of the silicate minerals can with the geochronology, based on their isotopic composition which can be determined. It will be mainly the systematic decay of 147 Sm to 143 Nd and 187 Re to 187 Os used. It makes reference to the huge database of isotopic data for which it can be said that the diamond formation at different times of all geological eras of time took place repeatedly, and there are not only old diamonds, which are more than three billion years, but there are also younger diamonds (O'Donoghue, 2003 ).

From the ratio of the stable isotopes of 13 C and 12 C, it allows one to draw conclusions about the origin of the carbon. Radioactive 14 C has a relatively short half-life. After 500,000 years, 14 C is almost completely disintegrated and natural diamonds as well as in natural graphite is no longer available now.

Social Issues

Small-scale mining is of great economic and social importance. It has been estimated that, worldwide, approximately 13 million people are directly employed ...