Per"i*do*tite (?), n. [Cf. F. p'eridotite.] 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.
© Webster 1913.