| 释义 |
smectite Min.|ˈsmɛktaɪt|
[See prec. and -ite1 2 b.]
a. A kind of fuller's earth. Now Obs. exc. Hist.
1811J. Pinkerton Petral. I. 278 [Iconite contains] a combination which nearly corresponds with the smectite of Cimolus. 1868Watts Dict. Chem., Smectite, a term..applied..more particularly to an argillaceous mineral from Cilly in Lower Styria,..and another from Condé in France. 1932Amer. Mineralogist XVII. 198 It seems hardly worth while to retain the two names smectite and montmorillonite for what appears to be the same mineral... It seems in the best interests of science to continue the name montmorillonite, and to drop that of smectite. 1942Ibid. XXVII. 810 The differential thermal curve for the smectite sample..is like that of montmorillonite... This is in agreement with Kerr's..conclusion [prec. quot.] that smectite is not a valid species because of its similarity to montmorillonite.
b. = montmorillonoid. So smectite group = montmorillonite group s.v. montmorillonite b.
1955G. Brown in Clay Minerals Bull. II. 296 Smectites is the name proposed for the minerals at present variously known as montmorillonoids, montmorins, minerals of the montmorillonite group and frequently even montmorillonites. Smectites are defined as minerals composed of 2:1 or triphormic layers, which, when the readily exchangeable cations are replaced by Na+ and the material is saturated with glycerol, give a basal spacing of 18Å approximately. 1957R. Greene-Kelly in R. C. Mackenzie Differential Thermal Investigation of Clays v. 140 By far the most abundant dioctahedral smectite is montmorillonite. 1966[see montmorillonite a]. 1975Amer. Mineralogist LX. 66/1 The significant chemical and physical properties of smectites often depend on the nature of the interlayer exchange ions. 1979Sci. Amer. Apr. 78/1 (caption) Smectite group of clay minerals, formerly called the montmorillonite group, has extremely fine-grained, irregular and thin-layered crystals. |