Metals and Mining Portfolio stalwart Glencore International (London: GLEN, OTC: GLNCY) has now won shareholder approval for its proposed takeover of Xstrata Plc (London: XTA, OTC: XSRAY). The arrangement also passed muster with European Union anti-trust regulators. That leaves only approval of anti-trust authorities in China and South Africa as hurdles to completing the deal to create the world’s-fourth largest producer of commodities by market capitalization.

Glencore, which already held roughly 33.7 percent of Xstrata, was forced to win over a range of other large owners, notably the sovereign wealth fund of Qatar. The latter in the end forced Glencore to raise its all-stock offer, even as Xstrata shareholders wound up voting down an arrangement to offer bonuses to Xstrata executives in return for staying on post-merger.

Failure of that measure to pass induced Xstrata Chairman Sir John Bond to resign effective with the merger’s close, which is still expected in early 2013. And it could also lead to the departure of other top staff, 70 of who would have received payments to stay.

Even in a worst case, however, the merger offers compelling economics for shareholders of both the acquirer and the acquired. Those include vast geographic and product diversification and unmatched ability to market output, all key advantages to weathering the ups and downs of a natural resources bull market that’s already older than its predecessor in the 1970s.

Recent developments include the launch of production at the Koniambo nickel project in New Caledonia in late November. Xstrata also announced its Antapaccay copper mine in southern Peru has begun to produce commercial grades and is rapidly ramping up to a target annual output rate of 160,000 tonnes of copper in concentrate.

As for the balance sheet, credit rater Moody’s has affirmed an investment grade rating and stable outlook for the combination. One big reason is opportunities for synergies by combining Glencore’s trading operation with Xstrata’s production and both companies’ pipelines of large mining projects. Another is Glencore’s still-to-be-completed purchase of the Australian and Canadian grain handling assets of Viterra Inc., expanding reach into that lucrative market.

Offsetting these strengths is the inherent volatility of the commodity business. But with improved scale and a deeper resource base, the approaching completion of this belated merger is another good reason to stay bullish on this portfolio holding. Glencore International is a buy up to USD14.50 through its American Depositary Receipt GLNCY.