Kimberlite and of those just over 30 have been economic enough to diamond mine. The deposits occurring at Kimberley, South Africa, were the first recognized and the source of the name. The Kimberley diamonds were originally found in weathered kimberlite, which was colored yellow by limonite, and so was called "yellow ground". Deeper workings encountered less altered rock, serpentinized kimberlite, which miners call "blue ground". See also Mir Mine and Udachnaya pipe, both in the Sakha Republic, Siberia. The blue and yellow ground were both prolific producers of diamonds. After the yellow ground had been exhausted, miners in the late 19th
Grammy Award for Best Rock Performance Grammy Award for Best Rock Performance The Grammy Award for Best Rock Performance is an award presented at the Grammy Awards, a ceremony that was established in 1958 and originally called the Gramophone Awards. According to the 54th Grammy Awards description guide it is designed for solo, duo/groups or collaborative (vocal or instrumental) rock recordings and is limited to singles or tracks only. This award combines the previous categories for Best Solo Rock Vocal Performance, Best Rock Performance by a Duo or Group with Vocal and Best Rock Instrumental Performance. The restructuring of these categories was a result of the