A rock made up of pyroclastic fragments that are at least 64 millimeters in diameter.
A pyroclastic rock in which all fragments are more than 2 mm in diameter.
pyroclastic rock consisting of angular volcanic fragments that are larger than 64mm in diameter and may or may not have a matrix.
Rock. Pyroclastic rock in which all fragments are more than 2 millimeters in diameter.
volcanic rock composed of lava fragments. Several origins, for example: flow breccia containing already solidified fragments of lava (auto-breccia); extrusion breccia resulting of semi-solidified magma uplift in the volcano vent; slope breccia on the volcano flanks...