I was looking at NGK plugs laser irdium and laser platinum, does it matter or would either one work?

 

Never-mind I think I answered my own question through research. Iridium seems to be similar to platinum, except harder and a higher melting point. Interestingly it is one of the rarest metals on earth save one or two others. Also due to these features it seems that the Iridium tip can be made smaller and it seems it may draw less power.