If it passes your visual inspection and sniff test, you could try it out and see how it works. I'd suspect, considering the above, it might be just fine.

But, I don't think I'd depend on it for accuracy unless you test it out and see how it works for reliability and consistency.

Depending on how it was stored, what's on the bottom may perform differently than what's on top! Might want to roll it around and mix it some after initial inspection.

I've used old powder of my brother's from the 1970s without issues!