I found this after detonating a nuke. It is noble gas conducting sparks but there is no plasma.
http://imgur.com/a/8lVL1
hydrogen fusion does that if there is a lot of hydrogen i've noticed. it just stays conductive and will sometimes pass on the sprk to metals, usually goes away after a while but it's weird
NBLE created due to HYGN's fusion won't turn into PLSM after being sparked. This is probably well known that this is special type of NBLE.