Black biwa pearl necklaces are made from the Biwa pearl. These are freshwater pearls originally from Lake Biwa in Japan not now referred to any pearl that has been cultivated in a freshwater mussel in Japan.
The Biwa is a mussel that resides in the Biwa lake in Japan.
Actually some pearls from china are incorrectly called Biwa pearls so if you are buying biwa pearls you need to get a certificate of authenticity to ensure they actually are biwa pearl and cultivated in a biwa mussel.
A black biwa pearl necklace is a beautiful sight and when browsing for one it is a good idea to keep in mind some important points.
Inspect the necklace and ensure that all the pearls are uniform in size. If possible roll the necklace on a smooth surface and note if it rolls straight or veers to one side. If it does veer then likely the pearls are no perfectly round but oval shaped.
Check the luster on each pearl. They should be uniform also. The holes for the string should be perfect and not ragged. The string should be strong and the pearls held in tight and not loose with too much string.
There is a heap of information on this site about pearls and how to select them. It is a good idea to browse the site and get as much information as you can.
If buying online, ensure you pick a reputable dealer and one who has a fixed address and contactable phone number. Ensure they have a returns policy so you can return any goods that are not as advertised or look different in the natural light at home rather than the picture on the screen. If the necklace is an expensive one it is a good idea to get it independently appraised for quality and value, especially if you are going to insure it.
Keeping the above in mind and you could be the proud owner of a beautiful black biwa pearl necklace.
You can see some great pearl necklaces at Zoara Pearls to give you a good idea of what is available.