don't mean to start this sil-- debate (some people's blood-pressure seems to be going higher and higher in this discussion/opinion/chat - call it what you may) on "Basra Pearls". However my understanding of "Basra" is that "Basra" was (& may be still is) a trading centre for pearls (& perhaps predominantly natural ones in view of Basra's vintage). It is also my understanding that the pearls traded in Basra originated from all over (Qatar, Bahrain, UAE, UAE, Kuwait, may be also from Iraq, Iran). There is nothing to suggest that traders from other countries (China, Japan etc) did not bring their "natural" pearls to Basra, only to ensure that they got a fair and competitive price etc. Therefore, given that a huge # of such pearls were then exported to Hyderabad and Mumbai (as the pearl centres of India), the term Basra was (has been, and is being) used in India for natural pearls traded at Basra.
Hence while I share Caitlin's opinion that Basra pearls could have originated anywhere, perhaps over 90% (just to quote a number) originated from the Gulf, back in those days (over 60-80 years ago). Since the natural pearls in majority came from the gulf, rejecting the term "Basra" is going a bit too-far, Caitlin. Again, that's my opinion too!