Business Insider5 年
What makes cultured and natural pearls so expensive
Natural pearls are hard to find ... To protect itself from the invader, the mollusk starts to coat the debris with nacre, or mother-of-pearl, the same material that lines the inner layer of ...
PBS5 年
The Culture of Freshwater Pearls
Most cultured freshwater pearls are composed entirely of nacre, just like their natural freshwater and natural saltwater counterparts. Throughout most of this century, the Japanese dominated the ...
Natural History Museum%2c London4 年
How do oysters make pearls?
Pearls are made by marine oysters and freshwater mussels as a natural defence against an irritant such as a parasite entering their shell or damage to their fragile body. The oyster or mussel slowly ...
来自MSN4 个月
From oysters to pearls: Know how the pearls are formed, types and difference between ...
The oyster’s response to these intruders is to encase them in nacre, leading to pearl formation. Natural pearls vary in size, with those exceeding 10 millimetres being rare and particularly ...
Natural History Museum%2c London1 年
The fish that's also a pearl
By secreting layers of aragonite and conchiolin, the same substances that are in its calcium carbonate shell, the mollusc creates a material called nacre, commonly known as mother-of-pearl. The oyster ...
Business Insider India5 年
Marie Antoinette's pearl pendant sold for a record-breaking $32 million. Here's why pearls ...
Natural pearls are hard to find ... To protect itself from the invader, the mollusk starts to coat the debris with nacre, or mother-of-pearl, the same material that lines the inner layer of ...