Search results
Results from the WOW.Com Content Network
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.
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.
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 ...
However, in reality most gem-sized natural diamonds are imperfect. The color of a diamond may be affected by chemical impurities and/or structural defects in the crystal lattice. Depending on the hue and intensity of a diamond's coloration, a diamond's color can either detract from or enhance its value.
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 ]
Diamonds were first discovered in Sierra Leone in the 1930s by British colonialists, with significant mining efforts beginning in 1935. [21] Sierra Leonean diamonds are renowned for their high quality, and retained a high value on the market. [22] The colonial government granted exclusive mining rights to the Sierra Leone Selection Trust (SLST ...
Diamond has been the leading component of the mineral sector ever since production of gems started being extracted by the mining company Debswana. [4] [5] Most of Botswana's diamond production is of gem quality, resulting in the country's position as the world's leading producer of diamond by value. [4]
A freshwater aquatic food web. The blue arrows show a complete food chain (algae → daphnia → gizzard shad → largemouth bass → great blue heron). A food web is the natural interconnection of food chains and a graphical representation of what-eats-what in an ecological community.