NOS Tube: Black Spot on Getter Flashing? Help

[madisonroberts]

Hello,
So i have a very large collection of vacuum tubes and i have been going through them to organize them. There are many instances where there are seemingly NOS tubes that have this small black teardrop shaped mark on the getter flashing. It would seem that this is from "burning" of the tube being used. These tubes test NOS, have their original boxes, have straight pins, all ink is intact, etc... I found this page that has made me think otherwise: TubeSound Blog Archive brown-black getter flashing does not mean ‘Used’!

I have also attached some of my own photos of these tubes. Could you guys clear this up for me.. It is quite annoying. Also, what is the main thing you look for to identify a used tube? Larger octal tubes are usually pretty easy to tell. ANY input on this subject would help me immensely. Thanks very much.

-Madison

[maton00]

they sometimes have some black markings in the glass over a near area where the heaters are located and that can tell you some about his life because they apear after some time. look were the heaters conect with the pins (were are solded) if that white stuff (the one that heater filament if covered) its blackened or too thin then you have something to worry about.

[TubeHead Johnny]

If they test new then what are you worried about? Have you tried them in a circuit?

[bear]

if the markings are browned, then the tube has been run for some time or has gotten too hot, or both. Otoh, if it tests good, it is good.

Tubes are not a beauty contest.

The way the getter is flashed is not a calm slow process... it's more like BANG!