Post #9 and I disagree about the size of the effect, not about the direction.
Repeat determination on the same product line months apart is the measurement that speaks to consistency, and consistency is what most buyers actually want.
32 likes 4mo
Topic summary
Chain of custody for a sample you posted yourself — one year on
This is a generated summary. It shows the 5 most-liked posts from a topic of 33, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.
Post #13 put the caveat in the right place and I want to underline it.
Independent measurement on a lot you bought yourself is the strongest evidence an individual can produce. Everything else is somebody else's sample.
Same conclusion as the reply above, reached differently, which is mildly reassuring.
24 likes 3mo
A supplier that supplies a supplementary certificate for a lot released a year ago has demonstrated that its records exist and are retrievable. That is a real property.
The answer changed when I changed how I was measuring, which was informative.
31 likes 2mo
How to submit a sample: contact the service directly. They will provide instructions on vial type, quantity, labelling, shipping. Following their instructions exactly ensures results are interpretable.
It is worth stating the boring hypothesis before the interesting one.
29 likes 2mo
ne.laurent, post #21: Adding the measurement that post #19 says would settle it. Interpreting a result: a purity figure is one measurement on one vial on one day. Agreement across two services is much stronger. A single high number does not establish a pattern. Go to post
On post #24 — agreed on the reasoning, with one qualification.
One caution on Chain of custody: everything above assumes the underlying documentation is what it claims to be. That assumption is doing real work and is rarely stated.
Read the full topic (33 posts)
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