peridotite

Definitions

  • WordNet 3.6
    • n peridotite a dark coarse-grained igneous rock consisting principally of olivine
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Webster's Revised Unabridged Dictionary
    • n Peridotite (Min) An eruptive rock characterized by the presence of chrysolite (peridot). It also usually contains pyroxene, enstatite, chromite, etc. It is often altered to serpentine.☞ The chief diamond deposits in South Africa occur in a more or less altered peridotite.
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Century Dictionary and Cyclopedia
    • n peridotite A rock composed essentially of olivin, with which are usually associated more or less of one or more of the minerals enstatite, diallage, augite, magnetite, chromite, and picotite. Linthologists are by no means agreed in regard to the nomenclature of the varieties of peridotite. M. E. Wadsworth distinguishes the following: dunite, composed almost entirely of olivin, with a few grains of picotite, magnetite, or some other accessory mineral: saxonite, a variety consisting of olivin and enstatite; lherzolile, of olivin with enstatite and diallage; buchnerite, of olivin, enstatite, and augite; eulysite, of olivin and diallage; picrite, of olivin and augite. Of these varieties, the first four have been found in meteorites as well as in terrestrial rocks; the others, so far as known, are exclusively terrestrial. Olivin passes readily into serpentine; hence many olivin rocks are found more or less completely altered into that mineral, so that the distinction between olivin and serpentine rocks is one not easily preserved. Peridotite is known to be in some cases an eruptive rock, and is generally supposed to have been such in all cases. That most serpentine rocks are the result of the alteration of some peridotic material is also generally conceded; that serpentine may have been produced in some other way is possible, but has not been distinctly proved.
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Chambers's Twentieth Century Dictionary
    • n Peridotite per′i-dō-tīt rock mainly composed of olivine
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Etymology

Webster's Revised Unabridged Dictionary
Cf. F. péridotite,

Usage

In literature:

Chromite is a common minor constituent of basic igneous rocks of the peridotite and pyroxenite type.
"The Economic Aspect of Geology" by C. K. Leith
Diabases and peridotites had been formed during the Lower Cretaceous in the San Luis Obispo region.
"Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 6" by Various
Peridotite and gabbro form much of the eastern peninsula (Banggai).
"Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 5" by Various
Serpentines, peridotites and diabases are interstratified with the Eocene deposits.
"Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 2" by Various
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In science:

Schroeder T, John B, Frost R (2002) Geologic implications of seawater circulation through peridotite exposed at slow-spreading mid-ocean ridges.
Magnetism, FeS colloids, and Origins of Life
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