It might as well be June, given the number of marriages being announced among global mining companies.

Indeed, for Fools who pay attention to the active minerals and mining sector -- as most should -- it probably seems like just the other day that BHP Billiton (NYSE: BHP), the biggest miner of them all was forced by regulators to throw in the towel on proposed deals with Potash Corp. (NYSE: POT) and its fellow Anglo-Australian miner Rio Tinto (NYSE: RIO). But that hardly ended the action in the industry. All of a sudden, miners and related companies are pairing up faster than teenagers on Sadie Hawkins Day.

Starting with the most significant of the newly-minted deals, Rio Tinto and Aluminum Corp. of China (NYSE: ACH) -- or Chinalco -- will team up to search for minerals in China, with their primary targets being copper and coking coal. Chinalco, which already has a 9% interest in Rio, will own 51% of the venture, with the remainder going to Rio. The three-to-five projects with which the companies will start off next year are expected to involve investments up to $10 million.

But the venture with Chinalco isn't Rio's only new activity involving a Chinese company. On Friday, the company also announced jointly with Sinosteel Corp., China's second-biggest importer of iron ore, that cooperation by the pair at the Channar iron ore project in Western Australia will be extended. These announcements follow a July agreement between Rio and Chinalco, under which the Chinese company will invest in an iron ore project in Guinea in which Rio is the controlling partner.

Lest you think that Rio is limiting its new relationships to deals with Chinese companies, it also appears that the company may be talking turkey regarding a $3.4 billion acquisition of Riversdale Mining, an Australian company that largely produces anthracite and coking coal in South Africa and Mozambique. Completing that deal may not be a slam dunk, however, since rumors have Brazil giant miner Vale (NYSE: VALE), among others, also eyeing all or part of Riversdale.

And there are even mining deals being announced that don't involve Rio. As last week came to an end, U.S.-based Walter Energy (NYSE: WLT) announced that it would buy Canada's Western Coal for $3.3 billion. That combination will result in a huge producer of metallurgical coal, which is used in steel manufacturing.

So the mining deals keep coming. Clearly they reflect an expanding demand for natural resources in developing nations like China and India. And while BHP has been quiet for a matter of weeks now, I fully expect that the biggest miner of them all will be chasing another acquisition in the weeks or months to come.

That, it seems to me, is ample reason for Fools to pay close attention to Rio and BHP, as the two miners continue to expand their already massive operations.