Quote Originally Posted by Kirk Keyes View Post
To set the record straight, I suggested that 20 Mule Team may contain impurities that would interfere with photgraphic uses, and that photo-grade borax gives one some assurance that your reagents are suitable for photographic uses.
I have refrained from posting in this thread until now. I feel that I have to clarify my position as well.

Kirk not only has his chemistry straight, he has also stated in this quoted post my own thoughts on this matter.

The most common impurities are halide salts and insoluable colloidal salts. Patrick has alluded to the latter in the past saying that some of his Borax solutions are cloudy and the cloudy suspension cannot be filtered out.

This whole thing may be summarized by saying that Patrick is trying to prove his point, that he can compound usable developers. That is conceded, but due to lack of full checks, we don't know how they compare in detail to off the shelf developers. In fact, in some test comparisons shown in other threads, I (and others) have given the tip of the hat to the commercial (albeit modified) developer.

I am not a borax chemist, but in private notes, I have exchanged similar, but less specific informaiton with Patrick discoraging him from the view that an ester or other type of compound is being formed. This was obvious to me, but the details were unclear and I had no text references for help. I thank Kirk for giving us the complete story on this.