Pearl or parasite enters a bivalve mollusk and settles inside the shell. The mollusk, irritated by the intruder, forms a pearl sac of external mantle tissue cells and secretes the calcium carbonate and conchiolin to cover the irritant. This secretion process is repeated many times, thus producing a pearl. Natural pearls come in many shapes, with perfectly round ones being comparatively rare. Typically, the build-up of a natural pearl consists of a brown central zone formed by columnar calcium carbonate (usually calcite, sometimes columnar aragonite) and a yellowish to white outer zone consisting of nacre (tabular aragonite). In a pearl cross-section
Pearl Rivers Pearl Rivers Eliza Jane Nicholson (formerly Holbrook; née Poitevent; March 11, 1843 – February 15, 1896), who wrote under the "nom de plume" Pearl Rivers, was a United States journalist and poet. She took the name from the Pearl River near her home in Mississippi. Eliza Jane Poitevent was born in Gainesville, Hancock, Mississippi, USA, on March 11, 1843 (some sources say 1849). She was the third child of a prosperous family of five, with a busy father and a sickly mother. She is listed on the 1850 U.S. Census as living in Beat 2 of Hancock County, Mississippi, with