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 Slaghoople to date is in the 1993 animated film "", in which she is voiced by Janet Waldo. Pearl Slaghoople appears in both live-action adaptations of the series: Pearl Slaghoople Pearl Slaghoople is a fictional character on the animated TV show "The Flintstones". She is the mother of Wilma Flintstone, who is married to Fred Flintstone. In the original series, she portrays Fred's stereotypically antagonistic mother-in-law, acting as a nagging irritant. Her appearance was similar to Wilma's, although Pearl was noticeably larger-figured, similar in build to the men of Bedrock rather than the more shapely Wilma and Betty. In the original