What is the collective noun of pearls?
That's an interesting one. The most common and widely accepted collective noun is a 'string of pearls'. This is what you would hear most often, particularly when they're arranged as jewellery. You could also correctly say 'a rope of pearls', which usually suggests a much longer or more lavish necklace. So, while 'string' is the classic answer, 'rope' is a perfectly good alternative depending on the specific arrangement of the pearls. Both are quite correct.
If pearls are scattered, you might call them a collection of pearls. But in English grammar, the most accepted is string.
Sometimes people also say a cluster of pearls when referring to loose pearls grouped together.
I’ve seen jewelers use the phrase strand of pearls, which is also correct in fashion industry.