For me i think gold or silver is more safe and i trust gold and silver more because i already feel the profit from investing in gold or silver and this kind investment already exist since old days, that's why this is more trustworthy.
They are buying gold and reducing US Dollar at the same time. They may see the future of US Dollar loses its value so they are trying to reduce the risk of having too much US Dollar.Then they also try to buy enough gold to back up their currency. This is all I heard.
That is for China