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
The Pearl Report The Pearl Report The Pearl Report is a public affairs programme aired on TVB Pearl from 1 April 1988 to 25 June 2018. The show mainly deals with current affairs in Hong Kong, although there are also stories concerning wider regional and international issues, often produced abroad. Locations covered include the United Kingdom, the United States, Australia, Germany, Russia, Malaysia, Canada, Oman, Vietnam, Thailand, Japan, the Philippines, the United Arab Emirates and all different parts of China. A broad spectrum of topic areas is covered on the Pearl Report, including political, social, health, education, human rights, economic and sport-related issues.