Min. [f. Gr. τεφρός ash-colored (f. τέφρα ashes) + -ITE1. Cf. L. tephrītis (Pliny) an ash-colored precious stone.) Name given to a class of volcanic rocks related to the basalts. Hence Tephritic a., pertaining to or consisting of tephrite; Tephritoid, a variety of tephrite containing no nepheline.
1879. Rutley, Stud. Rocks, xiii. 253. The tephrites, or those rocks which are characterised by the presence of nepheline or leucite in conjunction with plagioclase.
1889. Amer. Nat., April, 259. According to the predominance of one or other of the constituents they are divided into basaltic, doleritic and tephritic varieties.
