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
Parable of the Pearl Parable of the Pearl The Parable of the Pearl (also called the Pearl of Great Price) is one of the parables of Jesus. It appears in and illustrates the great value of the Kingdom of Heaven. It is the penultimate parable in Matthew 13, just before the Parable of the Dragnet. It immediately follows the Parable of the Hidden Treasure, which has a similar theme. It does not appear in the other synoptic gospels but a version of this parable does appear in the non-canonical Gospel of Thomas, Saying 76. The parable has been depicted by artists such as Domenico