See Also: tonalite(dictionary)

tonalite (iou)



tonalite noun. L19.
[from Tonal(e Pass, northern Italy + -ITE1.]
Geology. Orig., (a variety of) quartz-diorite. Now spec. a coarse-grained plutonic rock consisting essentially of sodic plagioclase, quartz, and hornblende or other mafic minerals.
tona'litic adjective M20.