I made a spreadsheet comparing vendor COAs — anyone have experience?

Dr.RenalNash said:

Shipping damage protocol for vendor vetting orders: if your package arrives with visible damage, temperature excursion, or broken vials: Photograph…

Agreed, and mass spec answers a question purity does not: identity. High purity tells you one thing dominates the chromatogram, not that it is the molecule you ordered. A mass within about a dalton of expected is the identity check.

Dr.NateNeph said:

Vendor reputation tracking for vendor vetting: I maintain a personal spreadsheet with every order I've placed — date, vendor, batch number, Janoshik…

Thank you for spelling out the reasoning rather than just the conclusion. Adding it to my notes with a link back to this thread.

From the other side of the consultation, briefly. It helps to ask what evidence would change your mind before you look at any. If nothing would, the discussion is not about evidence, and it is better to say so early than to spend nine posts discovering it.

That is the short version; the long version is somebody else's post.

VanRx_Mike said:

It helps to ask what evidence would change your mind before you look at any.

Mine went the same way, slower.

Moderator note: a couple of off-topic posts removed. No action needed from anybody.