BGS Linked Open Data

Charnockitic rock

Charnockitic rock [''] ['Charnockitic rock'] ['Rock, charnockitic - A type of coarse-grained normal crystalline rock. The charnockitic suite of rocks is usually characterised by the presence of orthopyroxene (or fayalite plus quartz, though in such assemblages fayalite is invariably altered) and, in many such rocks, perthite, mesoperthite or antiperthite. Primary hydrous minerals are generally absent. They are commonly associated with norites and anorthosites and are linked closely with high-grade metamorphic terrains. Despite being composed largely of feldspar and quartz, charnockitic rocks are generally melanocratic due to very dark feldspar crystals, which also have a characteristically greasy appearance. British Geological Survey Research Report RR/99/06, section 5.1. Examples (root name and qualifier): charnockitic granite, charnockitic monzonite, charnockitic tonalite.'] [''] ['', '', ''] ['CHARNR'] ['Charnockitic rock'] ['stable'] ['']