tufa Geol.
(ˈtuːfə, ˈtjuːfə)
Also 8–9 tuffa, 9 tufo, tupha.
[a. It. tufa, tufo:—L. tōfus, tōphus: see tophus; cf. tuff n.]
1. A generic name for porous stones, formed of pulverulent matter consolidated and often stratified. (See Note s.v. tuff n. 1.)
| 1777 G. Forster Voy. round World I. 586 The stone of which the statue itself is formed..being nothing but the red tufa which covers the whole island. 1789 J. Williams Nat. Hist. Min. Kingd. II. 382 There are great quantities of the concreted substance called tufa in many parts of Scotland. 1849 Dana Geol. iii. (1850) 241 The tufa is very friable, yielding easily to the fingers. |
spec. a. calcareous tufa: ‘a porous or vesicular carbonate of lime, generally deposited near the sources and along the courses of calcareous springs’ (Page
Geol. Terms, 1865).
Cf. tuff n. 1 a.
| 1811 Pinkerton Petralogy I. 518 note, At Bionnay there are houses built of a calcareous tufa, containing fragments of lime-spar, limestone, and slate. Ibid. II. 374 note, This [tufo] is the Italian and classical orthography. Tufa may be reserved for depositions merely aqueous. 1839 G. Roberts Dict. Geol., Tufa, or Calcareous Tufa.., a friable earthy deposit from calcareous springs. The more solid form is travertin. 1865 Livingstone Zambesi xi. 222 In the vicinity of the erupted rocks we usually meet soft calcareous tufa. 1867 Ansted in Brande & Cox Dict. Sc. etc., Tufa [is] a name applied in Italy to certain porous loose rocks... Volcanic Tufa is the material under which Pompeii was buried... Calcareous Tufa when consolidated passes into Travertine. |
b. volcanic tufa: see
tuff n. 1 b.
| 1770 Hamilton in Phil. Trans. LXI. 7 The Italians distinguish it by the name of tufa, and it is in general use for building. 1772 Nat. Hist. in Ann. Reg. 79/2 What is called here Tuffa..is the same that covers Herculaneum, and that composes most of the high grounds about Naples; it is..a mixture of small pumice stones, ashes, and fragments of lava,..hardened into a sort of stone. 1778 Phil. Trans. LXVIII. 2 The walls were..of a tuffa exactly resembling that of Naples and its environs. 1794 Sullivan View Nat. I. 84 The..mass through which the catacombs are excavated are all indurated tufa. 1811 Pinkerton Petralogy II. 374 Brochant..supposes that they become volcanic tufo. 1838 Murray's Hand Bk. N. Germ. 239/1 Composed..of tufa and scoriæ, exactly similar to that found on Vesuvius. 1862 Dana Man. Geol. i. 685 When rain or moisture from any source descends with the cinders, the mass forms tufa,—a stratified, somewhat earthy, granular..rock, of gray, yellowish-brown, and brownish colors. 1866 Lawrence tr. Cotta's Rocks Class. (1878) 89 Tufa is now principally used to denote an earthy compound of volcanic products of the most various kind. |
2. attrib. and
Comb., as
tufa cement,
tufa grotto,
tufa quarry,
tufa rock,
tufa stone,
tufa wall;
tufa-like,
tufa-paved adjs.| 1839 W. Chambers Tour Holland etc. 55/1 Andernach is an ancient walled town, and the seat of a considerable export trade in oven stones and *tufa cement. |
| 1910 19th Cent. Feb. 365 The piers were formed of *tufa-like Caux stone. |
| 1905 R. Bagot Passport i, The steep, *tufa-paved street. |
| 1891 Farrar Darkn. & Dawn xxiv, The overhanging sides of the *tufa quarry. |
| 1820 T. S. Hughes Trav. Sicily II. xv. 368 Some workmen were excavating a wine vault in the *tufa-rock. 1861 J. H. Bennet Winter Medit. i. viii. (1875) 229 The island [Capri] is of limestone—a healthier geological formation than the soft tufa rock of Naples. |
| 1793 Trans. Soc. Arts (ed. 2) V. 222 A *Tufa stone, found on the rocky banks of the Rhine. 1894 Daily News 22 Sept. 6/2 The columns..are generally of grey tufa-stone. |
| 1877 J. Northcote Catacombs i. iii. 45 He strengthened the friable *tufa walls of some of the galleries..by..arches of brick and stone work. |