Ultramafic rock but there are ultrapotassic and highly silica-under-saturated rocks with >18% MgO which can be considered "ultramafic". Ultrapotassic, ultramafic igneous rocks such as lamprophyre, lamproite and kimberlite are known to have reached the surface of the Earth. Although no modern eruptions have been observed, analogues are preserved. Most of these rocks occur as dikes, diatremes, lopoliths or laccoliths, and very rarely, intrusions. Most kimberlite and lamproite occurrences occur as volcanic and subvolcanic diatremes and maars; lavas are virtually unknown. Vents of Proterozoic lamproite (Argyle diamond mine), and Cenozoic lamproite (Gaussberg, Antarctica) are known, as are vents of Devonian lamprophyre (Scotland). Kimberlite
Grammy Award for Best Rock Instrumental Performance to Paul McCartney and the band Wings for "Rockestra Theme". From 1986 to 1989, the category was known as Best Rock Instrumental Performance (Orchestra, Group or Soloist). According to the category description guide for the 52nd Grammy Awards, the award is presented to artists "for newly recorded rock, hard rock or metal instrumental performances". As of 2011, Jeff Beck holds the records for the most wins, with six. Sting has received three awards, twice as a member of The Police -- although he had no part in the band's "Behind My Camel", the 1982 award winner which he did not