porphyritic, a.
(pɔːfɪˈrɪtɪk)
Also 7 -etick.
[ad. med.L. porphyrīticus, f. L. porphyrītēs porphyrite; so F. porphyritique. The classical L. was porphyreticus.]
Of or pertaining to the porphyry of the ancients; of the nature or structure of the porphyry of modern mineralogists; spec. containing distinct crystals or crystalline particles embedded in a compact ground-mass.
| [1387 Trevisa Higden (Rolls) V. 131 Þe emperour..made þerynne a fount stoon of a maner stoon þat hatte porphiriticus.] 1432–50 tr. Higden ibid., He made a fonte or baptistery of a ston porphiritike. 1656 Blount Glossogr., Porphyretick, belonging to red Marble, or purple. 1658 Phillips, Porphyretick, (lat.) belonging to Porphyrie, i. a fine reddish marble, streaked with diverse colours. 1799 Kirwan Geol. Ess. 303 It reposes on indurated clay, as this does on a porphyritic rock. 1862 Ansted Channel Isl. 6 Pinnacles of granitic and porphyritic rock would be seen to rise out of large rounded masses of similar rock. 1878 Lawrence tr. Cotta's Rocks Class. 80 The texture of a rock is termed Porphyritic when distinct crystals or crystalline particles are distributed through an otherwise compact principal mass or matrix. 1884 Dawson in Leisure Ho. June 356/2 Two sphinxes in the porphyritic diorite of Assouan. |
So porphyˈritical a. (Worcester 1846); hence porphyˈritically adv.
| 1879 Rutley Stud. Rocks xi. 198 The crystals which occur porphyritically in the different varieties afford us a very imperfect clue to these relations. 1882 Geikie in Nature 7 Dec. 121/2 Mica-schists, in which crystalline aggregates of mica have been porphyritically developed. |