Moody's has just called the bottom of the commodities rout

Moody's Investors Service has injected some fresh optimism into the global mining industry by changing its outlook for base metals to stable from negative, which basically means it believes prices for aluminum, copper, nickel and zinc have already bottomed out.

"We view prices for base metals as having likely bottomed following the sharp decline beginning late last year, and consequently we have revised our price sensitivity assumptions," said Carol Cowan, a Moody's senior vice president and author of the report.

The analysts believe that each base metal, with the exception of zinc, will remain oversupplied, which means prices will remain low until at least 2018, but Moody's they won't deteriorate any further.

The upward revision stems largely from economic stabilization in China, the world's largest consumer of raw materials, which recently launched a stimulus program aimed to boost its construction industry.

Though Beijing's spending has now slowed down, Moody's believes that commodity prices will hold onto their levels seen in the second quarter of the year.

The stable industry outlook reflects expectations for the fundamental business conditions in the industry over the next 12 to 18 months.