In geology, the term xenolith is almost exclusively used to describe inclusions in igneous rock entrained during magma ascent, emplacement and eruption.
Examples of xenocrysts are quartz crystals in a silica-deficient lava and diamonds within kimberlite diatremes.
Xenoliths of dunite, peridotite and spinel lherzolite in basaltic lava flows are one example.
Some kimberlites contain xenoliths of eclogite, which is considered to be the high-pressure metamorphic product of basaltic oceanic crust, as it descends into the mantle along subduction zones.
[7] The large-scale inclusion of foreign rock strata at the margins of an igneous intrusion is called a roof pendant.