Ampholite

It seems possible that the characteristic hydrated minerals of the postulated assemblage would be amphiboles and that the metamorphic grade in the top 20 km of the oceanic mantle might correspond roughly to various subfacies within the amphibolite facies. A convenient name for these hypothetical rock types would be ‘ampholite’ or amphibole-olivine rock.

The primitive nondifferentiated matter of the Earth's upper mantle may appear in the form of four varieties of pyrolite (plagioclase, spinel, pyroxene, or garnet pyrolite) or ampholite. The main minerals of pyrolite are olivine and pyroxenes, while ampholite is composed of olivine and amphibole.