Kimberlite garnets rich in chromium, are generally absent from most other igneous rocks, making them particularly useful as indicators for kimberlites. These indicator minerals are generally sought in stream sediments in modern alluvial material. Their presence may indicate the presence of a kimberlite within the erosional watershed that produced the alluvium. The geochemistry of Kimberlites is defined by the following parameters: Kimberlites are the most important source of primary diamonds. Many kimberlite pipes also produce rich alluvial or eluvial diamond placer deposits. About 6,400 kimberlite pipes have been discovered in the world, of those about 900 have been classified as diamondiferous,
Grammy Award for Best Male Rock Vocal Performance Originally called the Grammy Award for Best Rock Vocal Performance, Male, the award was first presented to Bob Dylan in 1980. Beginning with the 1995 ceremony, the name of the award was changed to Best Male Rock Vocal Performance. However, in 1988, 1992, 1994, and since 2005, this category was combined with the Grammy Award for Best Female Rock Vocal Performance and presented in a genderless category known as Best Rock Vocal Performance, Solo. The solo category was later renamed to Best Solo Rock Vocal Performance beginning in 2005. This fusion has been criticized, especially when females are not nominated