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.
<br /> <br /> Among the chief sources or mother of pearl are the pearl oyster, found in warm and tropical seas but the substance can also form in the shells of fresh water mollusks. <br /> <br /> Mother-of-pearl is the nacreous iridescent lining of a mollusk's shell.