Birch Mountains kimberlite field shales interbedded with kimberlite at some of the diatremes are consistent with a Late Cretaceous age (Late Albian to Maastrichtian). The volcanic rocks of the BM field consist primarily of crater-facies pyroclastic kimberlite and resedimented kimberlite. They include massive layers, as well as bedded and graded layers of coarse lapilli alternating with layers of finer tuff. Lapilli and olivine phenocrysts are set in a grey-green matrix of serpentine, carbonate minerals (calcite, dolomite and magnesite) and clay minerals. Phlogopite, oxide minerals (ilmenite, perovskite and spinel), apatite and pyrite are also present. Diamonds and microdiamonds have been recovered from samples taken from
Sometimes I Sit and Think, and Sometimes I Just Sit Courtney Barnett was announced as the winner of the 2015 Australian Music Prize award which is given for the best Australian album release of the year. Credits are adapted from liner notes of "Sometimes I Sit and Think, and Sometimes I Just Sit". Musicians Production Sometimes I Sit and Think, and Sometimes I Just Sit Sometimes I Sit and Think, and Sometimes I Just Sit is the debut studio album by Australian indie rock musician Courtney Barnett, released on 20 March 2015. The album received wide acclaim and was ranked as one of the best albums of 2015 by numerous