The Capital of China is, by far, the 3rd most populated city in the world. Having population of 21.5 million (21,516,000), with a population density of 1,300/km2, it is countryâs center for education, culture and politics. Talking about politics, this city is the hub of politics in the country for, as long as, eight centuries.
A pearl is an organic mineral mixture formed with the soft living tissue of a shelled mollusk.Chemically pearls are made of calcium carbonate, either the mineral aragonite or a mixture of aragonite and calcite, sometimes also with minor vaterite.Pearls are used as gemstones, but are not regarded as true minerals due to their organic origin. pearl is an organic mineral mixture formed with the soft living tissue of a shelled mollusk.
Mother-of-pearl is also known as nacre. Mother-of-pearl is used for jewelry, buttons, tiles, the production of faux pearls, and calcium (pearl) supplements. Mother of pearl is the iridescent substance that forms the lining of the shells of some fresh-water and some salt-water mollusks.