In the last year, shares in Rio Tinto (LSE: RIO) have fallen by around 27%. As such, many investors may feel as though the outlook for the company is rather downbeat, since investor sentiment has clearly worsened in recent months. And if commodity prices were to fall in future, it would be of little surprise for Rio Tinto’s share price to do likewise.

While Rio Tinto’s future is largely dependent upon the price of commodities, the company has a sound strategy to survive further weakness in this space. For example, it has cut costs and focused on becoming increasingly efficient so that it is now one of the most competitive iron ore miners in the world. Furthermore, it has a sound balance sheet and strong free cash flow which means that it is able to invest in its asset base to ensure that it at least maintains its relatively dominant position within the industry.

With Rio Tinto trading on a price-to-earnings growth (PEG) ratio of 1.4, it seems to offer excellent value for money given the quality of its asset base and its highly efficient business model. As such, and while further commodity price falls cannot be ruled out, it looks set to survive and prosper in the long run which makes now a sound moment to buy a slice of it.

Also adapting successfully to a lower commodity price environment has been Antofagasta (LSE: ANTO). Like Rio Tinto, it has sought to become more efficient and with the sale of non-core assets such as its water business, Antofagasta has strengthened its balance sheet and made its long term future more secure.

While the price of copper has come under pressure, the price of gold has performed well in recent months and this could cause a boost to Antofagasta’s bottom line. In fact, in the next financial year Antofagasta’s earnings are forecast to rise by 68% and with its shares trading on a PEG ratio of 0.8, it seems to offer a very wide margin of safety.

As with Rio Tinto and any other resources company, Antofagasta is highly dependent upon the prices of the commodities it sells. But with greater diversity than many of its peers and an improved financial outlook, it could prove to be a top notch performer.

Meanwhile, Rockhopper Exploration (LSE: RKH) has also sought to strengthen its financial position through the acquisition of Falkland Oil and Gas. This seems to have been a logical move for the company to take since it has resulted in a business with a stronger asset base and with greater growth potential. And with the Falkland Islands in particular having significant potential for long term oil production, Rockhopper remains appealing to less risk averse investors.

Of course, Rockhopper is a relatively small entity and it is highly dependent upon news flow in the short term at least. But with a somewhat diversified asset base and a sound strategy, it could be worth a closer look.

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Peter Stephens owns shares of Rio Tinto. The Motley Fool UK has recommended Rio Tinto. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.