Nixie
A nixie tube is a glass envelope with ten stacked numerals in it and one of them glowing. The nine you can still faintly see are what make it a nixie instead of an orange font.
The original
Six IN-14 tubes on a brass base. The glow is warm orange because that is what neon does at low pressure; the mesh in front of the numerals is the anode grid. Everything about the look is a consequence of how the thing worked.
Inside a real tube all ten digits sit one behind the other. The nine that are off catch the light from the one that is on, so they hang there as faint wire shapes. Leave them out and you have a glowing font, not a tube.
A near-white core, a saturated amber halo, then a wide soft bleed onto the glass and the surface behind it. Neon does all three at once, which is why a single drop-shadow never reads right.
Old tubes wobble a little as the cathode heats unevenly. Ours dips imperceptibly every few seconds — you will not notice it, but you would notice its absence.
Live previews
Counting on your device clock right now.
Questions
Yes — six tubes, HH:MM:SS. On the Lock Screen and in StandBy the seconds tube ticks live; on the Home Screen iOS refreshes on a budget, so it advances in steps.
It wants darkness, like the real thing. On a pale wallpaper try the LCD or Editorial faces instead.
The nixie face keeps the authentic neon amber. If you want green or blue tube glow, the neon family ships in azure, green and pink.
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