It's difficult to determine the origin of pearls from a couple of photos, but at first glance these appear to be natural Bahraini spinners. Being that age, set in white gold (or platinum) in the presence of 10 diamond makes this a premium piece.
The value of natural pearls is in the eye of the beholder, but I would strongly suggest these be examined by a gem lab.
There are a few experts here in Persian Gulf naturals and hopefully will weigh in on this piece.
I have a necklace that I purchased in India 19 years ago and have no idea what it might be worth if I try to sell it
Well qualified.I don't believe pearls are typically found in the Cyprea tigris?