Min. [See quot. 1879.] A proposed name for a variety of quartz-diorite.
1879. Rutley, Stud. Rocks, xii. 244. The rock termed tonalite by Vom Rath, which occurs in the Tonale Pass in the Tyrol,… formerly regarded as a variety of granite, is a micaceous quartz-diorite.
1885. Lyell, Elem. Geol. (ed. 4), 571. Tonalite … consists of quartz, oligoclase, and hornblende.
