One concrete data point for the thread. One practical note: write down what you did and when, before you need it. Reconstructing a timeline from memory three months later is how people end up unable to answer the one question that would have resolved it.
I would rather be corrected than agreed with, if it comes to it.
One thing that is still open after Dr.ReproEndo’s answer:
Whether a purity figure and a content figure can disagree without one of them being wrong?
raj_cambridge said:One practical note: write down what you did and when, before you need it.
Filing a mild objection. Mild because I might be wrong; an objection because nobody has addressed the case that does not fit. The objection nobody has made: this only works if the measurement is doing what we assume it is doing, and that assumption has not been tested here.
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Shop Reference Standardsraj_cambridge said:One practical note: write down what you did and when, before you need it.
Agreed, with the usual condition: that holds for the average and this board is a collection of individuals. A population claim and a personal prediction are different things and get quoted interchangeably.
Ask again with the specifics and you will get a better answer than this one.
Reporting back.
Purity and content being different measurements was the piece I was missing. The vial was overfilled and pure, which is a very different problem from the one I thought I had.