That greatly depends on the quality, size, and color, not to mention that one also has to establish first whether they are indeed natural or "real cultured" pearls.
Zeide can tell a lot from pictures, especially if they are not strung, show the holes in at least one picture. I have some natural pearls too, and Zeide was able to tell some interesting stuff from the pictures. I hope you read that thread- it is under natural pearls forum.......