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Webster 1913 Edition
Peridotite
Per′i-do-tite
,Noun.
[Cf. F.
péridotite
.] (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.