Kimberlite source of mined diamonds today. The consensus on kimberlites is that they are formed deep within the mantle. Formation occurs at depths between , potentially from anomalously enriched exotic mantle compositions, and they are erupted rapidly and violently, often with considerable carbon dioxideand other volatile components. It is this depth of melting and generation that makes kimberlites prone to hosting diamond xenocrysts. Despite its relative rarity, kimberlite has attracted attention because it serves as a carrier of diamonds and garnet peridotite mantle xenoliths to the Earth's surface. Its probable derivation from depths greater than any other igneous rock type, and
Grammy Award for Best Rock Performance Recording Academy's wish to decrease the list of categories and awards and to eliminate the distinctions between solo and duo/groups performances. The Academy argued that any distinction between these performances is difficult to make, as "four-fifths of rock acts are groups, and even solo rock acts tend to be backed by a band". From 2014, this category has also included hard rock performances that were previously screened in the Best Hard Rock Performance and Best Hard Rock/Metal Performance categories, which are now defunct. Grammy Award for Best Rock Performance The Grammy Award for Best Rock Performance is an award presented