Without anyone particularly noticing, gold has made an informal comeback as a de facto world currency. The currency vigilantes of Utah are, if anything, somewhat behind the times.

HONG KONG/SHANGHAI (Reuters) -Hong Kong's de facto central bank said on Thursday it bought US$1.2 billion worth of Hong Kong dollars after the local currency hit the weak end of its trading band.

Hong Kong authorities intervened for the fourth time in two weeks to prevent the city’s currency from weakening beyond its ...