greasing new spark plugs. copper or normal?

[Enceladus]

Currently replacing my spark plugs and seem to remember that its a good idea to pop a bit of grease on them.
What type is better?
Thanks

[Dead Eye]

A little bit of copper on the threads couldn't hurt I guess, but I wouldn't use anything else. The high temperatures from the engine will melt and destroy any other grease I expect and I wouldn't want to see the results...

[Enceladus]

thanks
thats what i thought but wanted to get other opinions

[JZS 600]

Always used a bit of engine oil, not failed yet

[sadlonelygit]

g'wan, dunk 'em in right up to the insulation.................just like one of my apprentices did!!!!!!!!!!!!

[garyb]

Copper for me too - never had any issues with it.

[VNA]

Don't fancy putting copper on em. 

I smear a tiny amount of graphite grease on then.  The grease carrier will burn off leaving the graphite behind.

To be honest there should be any need to use anything.