rhyolithic

Etymology
From +, presumably under influence from.

Adjective

 * : composed of or related to rhyolite.
 * 1) * 1884, "St Paul" in the Encyclopaedia Britannica, 9th ed., Vol. XXI, p. 189:
 * According to M. Vélain, the island originally rose above the ocean as a mass of rhyolithic trachyte similar to that which still forms the Nine Pin rock to the north of the entrance to the crater.
 * According to M. Vélain, the island originally rose above the ocean as a mass of rhyolithic trachyte similar to that which still forms the Nine Pin rock to the north of the entrance to the crater.