Porcelaneous—like porcelain.
Pore—a very small opening.
Posterior—situated behind; to the rear.
Precambrian—that portion of geologic time before the [Cambrian]; divided into [Archeozoic] era (Early [Precambrian]) and [Proterozoic] era (Late Precambrian).
Protero—combining form meaning fore, former, or [anterior] in time (Greek proteros, fore).
Proterozoic—youngest era of the [Precambrian]; follows the [Archeozoic] era and precedes the [Cambrian] [period] of the [Paleozoic] era.
Protista—the organic kingdom including the simplest of all one-celled organisms which possess various characters of both plants and animals; bacteria, algae, foraminifers, radiolarians.
Protoconch—in mollusks, the initial chamber of shell.
Pyrite—a hard, brass-yellow mineral composed of iron sulfide; “fool’s gold.”
Quaternary—the youngest [period] of the [Cenozoic] era, follows the [Tertiary] period.