Buffalo Head Hills kimberlite field grained, and well bedded, with high bedding angles. The reworked kimberlite is well sorted, distinctly bedded, and contains abraded olivine grains. Multiple layers of pyroclastic and reworked kimberlite separated by layers of marine mudstone are present at some pipes. These represent a series of discrete kimberlite eruption events separated by quiescent periods during which the muds were deposited. The majority of the BHH kimberlites are diamondiferous, in contrast to those of the Birch Mountains kimberlite field to the northeast which are mostly barren of diamonds. Based on petrography and whole-rock geochemistry, the BHH pipes are classed as Group 1A kimberlites.
Grammy Award for Best Female Rock Vocal Performance Originally called the Grammy Award for Best Rock Vocal Performance, Female, the award was first presented to Donna Summer in 1980. Beginning with the 1995 ceremony, the name of the award was changed to Best Female Rock Vocal Performance. However, in 1988, 1992, 1994, and since 2005, this category was combined with the Grammy Award for Best Male 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 female performers are not