Tschermakn.
/ˈtʃəːmak/ Mineralogy.
Used attributively and in the possessive to designate the synthetic pyroxene CaAl(AlSi)O6 as a hypothetical component of natural pyroxenes, or the part Al(AlSi)O6 of this.
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the world > the earth > minerals > types of mineral > silicates > inosilicates single chain > [noun] > pyroxene > Tschermak's molecule
Tschermak1943
1943 Amer. Mineralogist 28 73 The substitution Al2/MgSi is that by which the ‘Tschermak molecule’ is derived from diopside.
1962 Jrnl. Petrol. 3 355 The Cs may also be traced to the Tschermak's molecule in the high-CaO titaniferous clinopyroxene.
1970 Nature 26 Sept. 1337/1 Omphacite (diopsidic clinopyroxene in which jadeite predominates over Tschermak's molecule).
1974 Encycl. Brit. Macropædia XV. 322/1 Ferric diopsides contain ferri-Tschermak's molecule (CaFe2SiO6).
Derivatives
ˈtschermakite n. an amphibole end-member of the hornblende group, Ca2Mg3Al4Si6O22(OH)2, that is rich in aluminium; also, any member of the series this forms with ferrotschermakite (the other end-member).
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the world > the earth > minerals > types of mineral > silicates > amphibole (double chain) > [noun] > hornblende > varieties
smaragdite1804
antholite1806
anthophyllite1806
pargasite1818
fasciculite1823
dannemorite1857
grünerite1861
kaersutite1886
tschermakite1945
magnesiohornblende1978
1945 A. N. Winchell in Amer. Mineralogist 30 29 Hallimond notes that the second of these formulas is often called the Tschermak molecule; the writer would suggest that it be called tschermakite.
1966 W. A. Deer et al. Introd. Rock-forming Minerals ii. 168 Compositions approaching those of the edenite and tschermakite end-members are rare, and the compositions of the majority of the hornblendic amphiboles are intermediate between the two end-member series, tremolite—ferroactinolite and pargasite—ferrohastingsite.
tschermaˈkitic adj.
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the world > the earth > minerals > types of mineral > silicates > amphibole (double chain) > [adjective] > hornblende
hornblendic1823
tschermakitic1963
kaersutitic1968
1963 W. A. Deer et al. Rock-forming Minerals III. 272 Tschermakitic hornblendes.
1976 Nature 22 Apr. 673/2 The generally tschermakitic-pargasitic nature of all the amphiboles is like that of amphiboles produced synthetically from hydrous basaltic melts.
This entry has not yet been fully updated (first published 1986; most recently modified version published online September 2018).
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n.1943