hypersthene Min.
(ˈhaɪpəsθiːn)
Also hyperstene.
[ad. F. hyperstène (named by Haüy in 1803), f. hyper- 4 + Gr. σθένος strength; from its superior hardness as compared with hornblende, with which it was formerly confounded. The Eng. form is assimilated to the Greek.]
A silicate of iron and magnesium, of the pyroxene group, a greenish-black or greenish-grey mineral, closely allied to hornblende, often exhibiting a peculiar metalloidal lustre.
| 1808 T. Allan List Min. 37 Hyperstene. 1821 R. Jameson Man. Min. 132 Prismatoidal Schieler-Spar, or Hypersthene. 1849 Dana Geol. xvii. (1850) 632 The pearly crystallization of the light grayish-green hypersthene. 1862 Ansted Channel Isl. ii. x. (ed. 2) 259 Varieties of hornblende and hypersthene, with chlorites, serpentines and mica, all abound. |
b. attrib., esp. as hypersthene rock: = hypersthenite.
| 1838 Penny Cycl. XII. 412/1 Dr. M{supc}Culloch..first noticed Hypersthene rocks in Skye and Ardnamurchan. 1869 Contemp. Rev. XI. 366 The hypersthene mountains are painted in their real blackness. 1886 Pall Mall G. 4 Sept. 4/2 The Cuchullins are quite unlike any other mountain group..the coal-black ‘hypersthene’ rocks of which they are composed being only found in that district. |
Hence hypersthenic (haɪpəsˈθɛnɪk) a.1, related to or containing hypersthene.
| 1838 Penny Cycl. XII. 412/1 A dyke of Hypersthenic trap was noticed in Radnorshire. Ibid., Hypersthenic sienite. 1862 Ansted Channel Isl. ii. x. (ed. 2) 259 Most of the veins are filled up with hypersthenic rocks. 1876 Page Adv. Text-bk. Geol. vii. 127 The term hypersthenic granite is applied to an admixture of quartz and hypersthene, with scattered flakes of mica. |