. "Phonolitic-rock - A type of mafite. In the Rock Classification Scheme, this class includes phonolite and similar rocks. The term may be used as a field classification when an accurate mineral mode from thin section examination, or a chemical analysis, is not available. British Geological Survey Research Report RR/99/06, section 5.2 and figs. 17, 18."@en . . "stable"@en . "Phonolitic-rock"@en . "PNR"@en . . . . . . . "Phonolitic-rock"@en .