This may be a rhetorical question, but can new/nos tube looks used? I should think not -
Situation: recently received some minature 7-pin 6CY5 tubes that were claimed to be new. Each were in matching boxes (GE) that had signs of being opened (precumably to be tested). Each one had obvious darkening at the top nipple where the getter is. Tested on my calibrated Hickok, they all well exceeded the stated rating by 10-15% or so. They work in the circuit too.
For new tubes my expectation has been to expect super-shiny getters. While I'm not unhappy w/these; is it plausible these could be new given the discoloration in the getter?
I see this in nearly every new 7 and 9 pin miniature I encounter.
I think the dark spot is left over from the exhaust tip sealing process and has nothing to do with the getter.
Someone correct me if I'm wrong.