Wholesale pearl suppliers and other questions

Hello - I’m somewhat new to the jewelry business and very new to this
list…I was hoping to get some recommendations on good, reputable
wholesale pearl suppliers–preferably in the US.

Also–is it a common practice to buy things like pearls and
semi-precious etc., sight unseen except for photos in a
catalogue or on a website? The idea of purchasing these kind of
items that way makes me feel rather uncomfortable, and I know it
would be better to buy at a tradeshow where you can see for yourself
the actual items and their quality, but what do you do if you need
supplies before another tradeshow comes around?

If anyone can help with some recommendations and/or answers or
suggestions, I would be most grateful!

This seems like a great forum and a great resource–thank you!