I found a champion wandering around with the Aristocrat profession.  The ability said it increased the production bonus of any city the champion was in by 10%.  What is this production bonus?

Another some what related question.  Mining bonuses from Sovereign profession and the Mining Guild tech, does that also effect gold mines or is that just metal mines such as iron?  Gold is a metal as well but I do not know if those bonuses apply since the game treats gold as something separate.