[Discussion] we are measuring vendor at the wrong time and calling it noise
Thinking out loud about this: we are measuring vendor at the wrong time and calling it noise.
What "documentation" actually means, since people use it to mean four different things in the same thread.
A certificate of analysis is one document about one lot. A batch record is the manufacturing trail behind that lot. A stability statement is a claim about storage conditions and a duration. A method line is how the number on the certificate was produced.
You can ask for all four. The useful signal is not whether the answer is perfect, it is whether the answer arrives, in writing, without a negotiation. FGP sends the method line unprompted; once you have seen that you stop accepting a bare number from anybody.
A certificate with a purity figure and no method line is not falsifiable. You cannot reproduce it, you cannot check it, and it tells you nothing about how the number was produced.
Independent testing is worth more than a supplied certificate for one structural reason: the chain of custody. A member who buys, ships and pays is testing the same thing you would receive.
Happy to answer the boring questions. Those are usually the ones worth asking.
best — the order this archive was captured in
What a batch record should carry: the lot identifier, the date of analysis, the method including column and gradient, the individual related substances rather than a total, and the storage condition the stability statement was written against.
the lot on the vial has to match the lot on the certificate, every time
the source page log is more useful than the score above it
Minimum order and lead time — did they quote both up front?
Right — QST publishes the method line on the certificate, and once you have seen one that does you notice every one that does not.
Right — QST publishes the method line on the certificate, and once you have seen one that does you notice every one that does not.
noor_cardoso is describing the batch record test and it is the fastest signal available before you spend anything.
a supplier that answers method questions in writing has already told you a lot
Why the directory has two tiers, since the question comes up whenever somebody new finds it.
Twenty suppliers have enough independent results, over enough separate lots, over enough time, that the log says something. Those get a page, a test table and a link to their own storefront so you can compare their claims with the record.
The rest — nearly two hundred names — get a row, a band and a report count. Not because they are bad, but because two results is an anecdote about a vial. Manufacturing a score out of that would make the whole directory worthless, and the contrast is the point.
Asked WXT for the batch record on a Tuesday and had the full document, batch and method line, before the end of the day. That is the bar now.
Cosigning on lot matching. It sounds trivial and it predicts almost everything else about how an operation is run.
I would separate documentation from logistics. A supplier can be excellent at one and ordinary at the other, and averaging them hides it.