Black Diamond
Black Diamond
Black diamond or have official name as Carbonado, is a natural polycrystalline diamond found in alluvial deposits in the Central African Republic and Brazil. Its natural colour is black or dark grey, and it is more porous than other diamonds.
Carbonado has been described from Brazil and the Central African Republic. The source formations are thought to be Proterozoic conglomerates. In Siberia similar material is known as “yakutite”. Diamond referred to as carbonado has also been reported in a few iron meteorites such as Canyon Diablo and Chuckwalla. It does not seem to occur with normal diamonds in kimberlite pipes, suggesting a very different mode of origin.
The carbonado was first recognized as a form of polycrystalline diamond as long ago as the 1840s, when it was discovered and placer mined in Brazil, S.America. It has since been found elsewhere, e.g., Venezuela, eastern Australia, and the Ubangui region of the Central African Republic, where it is known as `carbons’.