All this would do is crash the gold price. Also note that all the gold at our disposal right now (worldwide) basically fits into a cube with 20m edges (its not as much as you might think).

Gold is not suitable to replace steel as building material (because it has much lower strength and hardness), nor copper/aluminium as conductor (it's a worse conductor than copper and much worse in conductivity/weigth than aluminium). The main technical application short term would be gold plated electrical contacts on every plug and little else...