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Andesite (/ˈændəzaɪt/) is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite.

A batholith (from Ancient Greek bathos 'depth', and lithos 'rock') is a large mass of intrusive igneous rock (also called plutonic rock), larger than 100 km2 (40 sq mi) in area, that forms from cooled magma deep in Earth's crust.

Pumice ( /ˈpʌmɪs/), called pumicite in its powdered or dust form, is a volcanic rock that consists of highly vesicular rough-textured volcanic glass, which may or may not contain crystals. It is typically light-colored.

Latite is an igneous, volcanic rock, with aphanitic-aphyric to aphyric-porphyritic texture. Its mineral assemblage is usually alkali feldspar and plagioclase in approximately equal amounts.

Rhomb porphyry is a volcanic rock with gray-white large porphyritic rhombus-shaped phenocrysts of feldspar (commonly anorthoclase) embedded in a very fine-grained red-brown matrix.

Bytownite is a calcium rich member of the plagioclase solid solution series of feldspar minerals with composition between anorthite and labradorite. Like others of the series, bytownite forms grey to white triclinic crystals.

Oligoclase is a rock-forming mineral belonging to the plagioclase feldspars. In chemical composition and in its crystallographic and physical characters it is intermediate between albite and anorthite.

Mordenite is a zeolite mineral that is one of the six most abundant zeolites and is used commercially. It was first described in 1864 by Henry How.

Stishovite is an extremely hard, dense tetragonal form (polymorph) of silicon dioxide. Large natural crystals of stishovite are extremely rare and are usually found as clasts of 1 to 2 mm in length.