Also 6–7 talke, 7–8 talck, 7–9 talk. [a. F. talc (Palissy, a. 1590) or ad. med.L. talcum, = Pg., It. talco, Sp. talco, talque, ad. Arab. ṭalq, mentioned A.D. 869 by Jahiz of Bassora, and by Serapion the elder (Syriac and Arabic), Rhazi, Avicenna, Ibn-el-Beithar † 1248, etc. Held by Arabic scholars to be from Persian, where the form talk. So Ger., Da., Sw. talk; Du. talk, talksteen.
In med.L., Matth. Silvaticus Pandectarum Opus, c. 1317, has talk; later writers have talcum; Matthiolus Comment, in Dioscoridem, 1549, has talchus; Agricola, 1546, talk.]
A name applied by the Arabs and mediæval writers to various transparent, translucent, or shining minerals, as talc proper, mica, selenite, etc. Now restricted to the following:
1. In popular and commercial use, (loosely) applied to (or including) MICA or Muscovy glass.
1601. Holland, Pliny, XXI. xiv. (1634), II. 95. Many haue made them [bee-hives] of Talc [orig. speculari lapide], which is a kind of transparent glasse stone, because they would see through them how the Bees do worke and labor within.
1644. Digby, Nat. Bodies, xxviii. 252. The gallery windows of my cabin … were of light moscovia glasse or talke.
1780. Coxe, Russ. Disc., 216. The windows … on account of the dearness of glass and Russian talk are generally of paper.
1866. Livingstone, Last Jrnls. (1873), I. vi. 157. Granite with large flakes of talc.
1867. J. Hogg, Microsc., I. i. 7. He fitted them on a little plate of talc, or thin-blown glass.
b. With a and pl. A plate of mica used as a microscopic slide.
1761. Stiles, in Phil. Trans., LV. 254. Many of the rings were broke … by some confinement of the talks. Ibid., 255. A third observation was made … of some blood dropped upon a single talk.
c. 1790. Imison, Sch. Art, I. 223. ’Tis proper to have some sliders furnished with talcs.
2. Min. A hydrated silicate of magnesium, usually consisting of broad flat laminæ or plates, white, apple-green, or yellow, having a greasy feel, and shining luster, translucent, and in thin plates often transparent; it exists in three varieties—foliated, massive (steatite or soapstone), and indurated (talc slate or schist).
1610. B. Jonson, Alch., II. v. With the calce of egge-shels, White marble, talck.
1668. Wilkins, Real Char., 62. Fissil, into Flakes,… Selenite, Muscovia glass, Isingglass, Sparr. Talc.
1681. Grew, Musæum, III. I. v. 308. A piece thus figur’d, I call A Crystal of Talk.
1770. Cook, Voy. round World, II. vi. (1773), 401. Some particular place where they [the Indians] got the green talc or stone of which they make their ornaments and tools.
1811. Pinkerton, Petralogy, I. 177. The mica may pass into talc or steatite, or siderite, as on the summit of Mont Blanc.
1862. Dana, Man. Geol., § 66. 61 Talc—Infoliated masses; folia flexible but not elastic; also compact, massive, very soft, and having a greasy feel.
1865. Bristow, Figuier’s World bef. the Deluge, ii. 38. The Serpentine rocks are a sort of compact talc.
1867. Brande & Cox, Dict. Sci., etc., s.v., Talc forms the basis of the rouge used by ladies; it is also employed by tailors for marking lines on cloth, and in a powdered state for making gloves and boots slip on easily, and to diminish the friction of machinery.
b. A species or variety of talc, or a mineral so called.
1794. Sullivan, View Nat., II. 93. We see crystals,… even metals, talks and asbestos, growing from stony substances.
1796. Morse, Amer. Geog., I. 460. Talks of various kinds, white, brown, and chocolate coloured crystals.
† c. Oil of talc, a preparation formerly used as a cosmetic, reputed to be obtained from talc. Obs.
1582. Hester, Secr. Phiorav., III. lxxxiii. 110. If this [verjuice] bee mixed with Oile of Talke, it will restore the sight vnto those that are almost blinde.
1610. B. Jonson, Alch., III. ii. You restore [her face] With the oyle of Talck.
1639. J. Mayne, City Match, II. i., in Hazl., Dodsley, XIII. 225. Who Do verily ascribe the German War … to curling, False teeth, and oil of talc.
[1678. Phillips (ed. 4), Talc, a squamous, white, and lucid stone, of which is made an oil, with which Women that are curious to preserve their beauty use to wash their faces.]
1727–41. Chambers, Cycl., s.v., Some chymists … pretend to draw from it that precious oil … called Oil of Talc, which is supposed a wonderful cosmetic.
3. attrib. and Comb., as (from 2) talc crystal, earth, rock, stone; talc-like adj.; esp. in names of mineral substances consisting partly of talc or containing magnesia, as talc-alum, -apatite, -chlorite, -garnet, gneiss, -iron-ore, -ironstone, -spar, -steatite; talc powder, powdered talc, talcum powder: see TALCUM; talc schist, talc slate, a schistose rock consisting largely of talc; (from 1) talc light, a window glazed with mica, or a lantern with mica instead of glass; so talc-windowed.
1868. Watts, Dict. Chem., V. 656. *Talc-alum, a term sometimes applied to magnesio-aluminic sulphate. Ibid., *Talc-apatite, a variety of apatite containing magnesia. Ibid. *Talc-chlorite, syn. with Clinochlore.
1681. Grew, Musæum, III. I. v. 310. A Diamond-square, i. e with unequal Angles, and equal sides; whereas in a *Talk-Crystal, both are unequal.
1861. H. W. Bristow, Gloss. Mineral., *Talc earth, Native.
1868. Watts, Dict. Chem., V. 656. *Talc-garnet, magnesian garnet from Arendal in Norway. Ibid. *Talc-iron-ore, Magnesian Iron-ore,… an iron-ore … consisting … of ferrous oxide with much magnesia. Ibid. *Talc-ironstone, Breithaupt’s name for a magnetic iron-ore from Sparta in New Jersey.
1808. Pike, Sources Mississ., III. 207. In one or two houses there were *talc lights.
1866. Blackmore, Cradock Nowell, li. The rim of dazzled vision whitened to a *talc-like glimmer.
1895. Syd. Soc. Lex., s.v. Powder, *Talc powder.
1681. Grew, Musæum, III. I. v. 309. A lump of the *Talk-Rock near Spiral, in the upper Carinthia.
1839. Ure, Dict. Arts, 747. It is … among the oldest *talc-schists and clay slates, that it usually occurs.
1866. Lawrence, trans. Cotta’s Rocks Class. (1878), 244. Talc-schist is almost always stratified, and forms alternating beds with other crystalline schists.
1832. Macgillivray, trans. Humboldt’s Trav., xxvi. (1836), 392. A primitive clay-slate passing into *talc-slate.
1834–5. J. Phillips, Geol., in Encycl. Metrop., VI. 560/2. Gneiss rocks … include among them many gradations, chlorite slate, talc slate, hornblende slate [etc.].
1681. Grew, Musæum, III. I. v. 309. A Green *Talk-Spar … brittle as Glass.
1756–7. trans. Keysler’s Trav. (1760), IV. 407. A kind of yellow green and whitish *talc-stone dug about Bern.
1888. Lees & Clutterbuck, B.C. 1887, xix. (1892), 206. An evil-smelling, *talc-windowed American stove.
