I missed that you were tossing the first leaching of the tech grade borax on the first reading myself. I did not find it clearly stated it was discarded. Anyway...
Originally Posted by gainer
I still have issues with using saturated solutions as a form of calibration. It's just so tricky using them as thye are so dependant on temperature. It's just so much simpler to weigh something out and dissolve it in solvent. I can't think of any analytical procedures where a saturated solution of anything is used as a "calibrated" solution. They are usually used as a reagent solution that is being added to a solution in order to supply an excess of a reagent, never to supply a precise amount. If you are careful and use good temperature controls and make sure you don't get your solution too cool and crash out your reagent, you could use a saturated solution as you describe.
But it really looks like a pain... Just buy a grade of high quality reagent and work from there. None of these mechanations to turn a sow's ear into a silk purse. (There, I was able to tie it back in with your ham comment!)