Australia's BHP Billiton (NYSE: BHP), the world's largest mining company and an increasing factor in oil and gas production, just unearthed its results for the past six months.

For the half-year, the company generated net profits of $10.52 billion, up 72% from the $6.14 billion for the same period in 2009. Revenue increased 39% to $34.17 billion. At the same time, the company increased its margins substantially, with its underlying EBITDA margin and attributable profit, excluding items, increasing by 60% and 88%, respectively.

As the company noted in releasing its results, "An improving economic backdrop and broader supply constraints continued to support the fundamentals for the majority of BHP Billiton's core commodities. Stronger realized prices … increased underlying EBIT by $8.5 billion, net of linked costs."

BHP achieved record iron ore shipments for the period, reflecting an increase in the company's Western Australia iron ore growth projects. Exports of that product for the company -- a key ingredient in steel manufacturing -- increased to 148 million tons on an annualized basis. BHP, Brazil's Vale (NYSE: VALE), and Anglo-Australian Rio Tinto (NYSE: RIO) are the world's primary suppliers of iron ore, much of which gets sold to steel manufacturers in China.

During the period, BHP and Rio Tinto attempted to form a joint venture combining their iron ore operations in Western Australia. However, European regulators blocked the effort in October. At the same time, BHP offered nearly $40 billion for PotashCorp (NYSE: POT), the world's largest supplier of potash, which is used in the production of fertilizer. However, Canadian regulators shot down that effort, too. The company is now developing its own potash operation in Saskatchewan.

BHP was hurt by the reduction in Gulf of Mexico oil and gas drilling, following the April tragedy involving BP (NYSE: BP) and Transocean (NYSE: RIG). As the company noted, however, "BHP Billiton was … one of the first operators to return both of its deepwater rigs to (water injection) drilling operations" in the Gulf.

Looking ahead, BHP is "cautiously optimistic" on the short-term future of the world's economy, reporting signs of a sustainable recovery in "major developed economies such as the United States." By the end of next year, the company anticipates buying back $5 billion of its shares.

I recently reiterated my belief that BHP is strong enough company to serve as a core holding in well-structured investment portfolios. Its results for the second half of 2010 have hardly altered that opinion. I encourage Fools to keep BHP firmly within their sights by adding it to My Watchlist.