It's a goldbug myth, a complete and utter fallacy that gold cannot go below the cost of production. Have a talk to the Venezuelans, they're currently flogging off 365 tons of gold because they can't make ends meet because the oil price is well below the cost of production and has been for ages, and hedge funds are also selling 430 tonnes due to the employment data.
There's no shortage, there's schiffloads of it, it doesn't get used up, it gets recycled and atm there's a surfeit of scrap which is also weighing on the price.
World production is increasing each year, gold's going below US$1,000, probably well below.