The American Pearl Company is the one to write about. The LsTendresse family have made numerous contributions to pearls in many different ways. The other "Am Pearl", also began in the 50's but has contributed some really inaccurate info to the field. While they do well as sellers- to some degree, they have been known to borrow stuff from others w/o asking, their pearl scholarship is among the worst I have seen.
Neither company bothers with "beads" except the ones inside the cultured pearls. AM Pearl Company cultivated American river fw pearls with nuclei- the other is a commercial company that doesn't have American river pearls in its sight and never did.