Heee~yyy, is that a "kuwabara, kuwabara" out of Seren in the second panel? :D

Incidentally, silver is a very good conductor of electricity as well, but is more expensive than copper, and not as good as gold, so it's almost never used for that purpose.

Further, if Ginka really is that good a conductor of electricity, she has nothing to fear - it is RESISTANCE to electricity that causes electrical energy to turn into the heat that actually kills you, if the electricity is conducted near-perfectly through your body, it'll go through you as harmlessly as the electricity flows through a copper wire, without doing any damage.