Gentlemen, I finished off a bottle of Unique on .44 spl loads, and got into a full bottle that was given to me a couple years back by my dad’s friend who has quit reloading. It’s got an orange label, unlike the current production powder. The seal was already broken, and when I dumped some in my powder measure, I noticed it’s a mixture of flake and coarse black stick powder, about 80/20 by volume.
I compared the sticks with my H4895 and IMR4198. It’s not a match, so the contamination happened elsewhere. It is thoroughly mixed with the flake powder, like its been intentionally mixed.
I’m ready to destroy it, unless someone can convince me that Alliant used to mix two types of powder back in the day...