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Similarly, natural diamonds usually have minor imperfections and flaws, such as inclusions of foreign material, that are not seen in synthetic diamonds. Screening devices based on diamond type detection can be used to make a distinction between diamonds that are certainly natural and diamonds that are potentially synthetic.
A natural material is any product or physical matter that comes from plants, animals, or the ground which is not man-made. [1] [2] Minerals and the metals that can be extracted from them (without further modification) are also considered to belong into this category. Natural materials are used as building materials and clothing. Types include:
“Natural diamonds are formed over billions of years, deep within the earth, through a process involving high pressure and temperature—usually in the presence of other minerals and gasses ...
Diamonds have high monetary value as one of the best-known and most sought-after gems, and they have been used as decorative items since ancient times. The hardness of diamond and its high dispersion of light—giving the diamond its characteristic "fire"—make it useful for industrial applications and desirable as jewelry. Diamonds are such a ...
Some irradiated diamonds are completely natural; one famous example is the Dresden Green Diamond. [11] In these natural stones the color is imparted by "radiation burns" (natural irradiation by alpha particles originating from uranium ore) in the form of small patches, usually only micrometers deep. Additionally, Type IIa diamonds can have ...
The carbon allotropes diamond and graphite have vastly different properties; diamond is the hardest natural substance, has an adamantine lustre, and belongs to the isometric crystal family, whereas graphite is very soft, has a greasy lustre, and crystallises in the hexagonal family. This difference is accounted for by differences in bonding.
Carbonado, commonly known as black diamond, is one of the toughest forms of natural diamond. It is an impure, high-density, micro-porous form of polycrystalline diamond consisting of diamond, graphite , and amorphous carbon , with minor crystalline precipitates filling pores and occasional reduced metal inclusions. [ 1 ]
Africa has a large quantity of natural resources, including diamonds, sugar, salt, gold, iron, cobalt, uranium, copper, bauxite, silver, petroleum, natural gas and cocoa beans, but also tropical timber and tropical fruit. Recently discovered oil reserves have increased the importance of the commodity in African economies.