Define vertebrate: any of a subphylum (Vertebrata) of chordates that comprises animals (such as mammals, birds, reptiles, â¦ â vertebrate in a sentence any of a subphylum (Vertebrata) of chordates that comprises animals (such as mammals, birds, reptiles, amphibians, and fishes) typically having aâ¦ See the full definition
Definition of LIGNITE. : a usually brownish black coal intermediate between peat and bituminous coal; especially: one in which the texture of the original wood is distinct âcalled also brown coal.
Rhyolite is an extrusive igneous rock with a very high silica content. It is usually pink or gray in color with grains so small that they are difficult to observe without a hand lens.Rhyolite is made up of quartz, plagioclase and sanidine, with minor amounts of hornblende and biotite.Trapped gases often produce vugs in the rock. These often contain crystals, opal or glassy material.t is usually pink or gray in color with grains so small that they are difficult to observe without a hand lens. Rhyolite is made up of quartz, plagioclase and sanidine, with minor amounts of hornblende and biotite. Trapped gases often produce vugs in the rock. These often contain crystals, opal or glassy material.