1848 Mining Jrnl. 4 Nov. 521/1 Mr. Twining's object is to form, by chemical means, a comprehensive series of petreous substances which he proposes to designate..pyrolite or artificial lava, as..being of igneous origin.

1962 A. E. Ringwood in Jrnl. Geophysical Res. 67 860/1 Immediately below the M discontinuity, the mantle consists dominantly of dunite and peridotite... This zone passes downward..into the primitive ‘pyrolite’. [Note] Peridotite is an unsatisfactory name for the hypothetical primitive mantle material, chemically equivalent to 1 part basalt plus 4 parts of dunite. Since a rock of this composition would crystallize dominantly as a mixture of olivine and pyroxene, the name ‘pyrolite’ is suggested.

1975 Sci. Amer. Mar. 56/1 Assigning an appropriate chemistry to the residual peridotite, one arrives at the hypothetical composition of the upper mantle. Pyrolite (pyroxene-olivine rock) is the name given to one of these hypothetical peridotites.

1990 P. Kearey & F. J. Vine Global Tectonics ii. 26 Pyrolite can exist in four different forms... The normal form existing to a depth of 70 km is pyroxene pyrolite, which transforms into garnet pyrolite at depths of 80–350 km.