spark gap material

Thread Starter


Joined Nov 25, 2018
how does gold hold up as a spark gap material for something like a tesla coil?

wouldn't the electrodes become very small after a small amount of usage?


Joined Sep 7, 2010
No idea ... but I can brain storm it ..... what are the mechanisms that could degrade terminals ??

Well there's oxidation ... or perhaps reacting with nitrogen in the air ... Gold will do none of these , very inert.

Then there's loosing atoms themselves through "evaporation" for want of a better term .. this must be related to the Melting point / boiling point of the metal .... and gold is not high or low , about 1000C but it is very thermally conductive which must help keep the temperature of the sparking area low ...

I would think gold would be good , if degradation did occur then very fine (mono atomic?) particles could be released into the air.. interesting stuff , search "mono atomic gold"

Silver might also be OK.


Joined Jun 4, 2014
This should give some clues. It relates to relay contact material. Relay contacts can arc and so arc resistance is important for higher power and especially for inductive loads.

Choose tungsten if you can.


Joined Nov 18, 2012
Nickel, platinum, palladium and iridium are all metals with high melting points and are used frequently with spark plugs but tungsten surpasses all of them as Albert has pointed out by almost double the melting point.