Just saw your email, Casey. Sorry did not see it before. I just came back to place this link to the untreated section:
http://www.pearlparadise.com/freshwater-pearls-special1.html
I figured this would be a good place to put it as anyone who really liked the pictures would be following this thread.
Treatments!
Freshwater pearls universally go the factory after harvest. But what happens there can change. There are three factory levels in freshwater. Some factories combine all three levels, others just one or two, others just one aspect of a single level.
The first level is the material factory. Here the pearls are separated for size.
The second level is also a material level. Here pearls are separated for shape and often quality. These two levels are often combined, and this is where you need to purchase if you want untreated goods. Here the pearls have only been washed.
The third level is where the processing takes place. After this stage the pearls are likely treated. The caveat is that you cannot purchase in an earlier stage unless you have the third stage available to you. You can contract this, but it is a volume game.
In the third level the pearls are drilled, bleached, treated for luster, and matched on temp strands and hanks. The bleach treatment you are all aware of, the luster involves heat and chemicals.
Basically every freshwater strand you will ever see has gone through the same process unless (big unless) they were purchased before process (not drilled, not matched) and kept unprocessed intentionally.