However, the reason why gold would spike on the back of 2 Iranian politicians dying is because of the political ramifications. If it is demonstrated that they died as a direct result of Israeli actions eg proxy or direct attack, then the gloves will come off and Iran will respond. This will greatly expand the war in the middle east and effect world trade. There is a strong chance the middle east will be the flashpoint which ignites a hot war around the world.
As always, gold is seen as the best safe haven asset in times of turmoil and the subsequent demand driven increase in price of Gold is a direct consequence.