The Globe and Mail reports in its Tuesday, Nov. 5, edition that domestic materials stocks have endured a drubbing of almost 30 per cent this year. The Globe's Scott Barlow writes that a sell-off combined with declining risks makes this an ideal time to search for investment value in the sector. Mr. Barlow says cash flow is king when filtering through mining stocks (earnings can be distorted by depreciation and other factors). He sorted stocks by their trailing 12-month price-to-cash flow. Then he took the cheapest stocks based on cash flow and ranked them by forward price-earnings ratios (based on analyst estimates). Mr. Barlow likes Rio Alto Mining ($1.73). It is a small speculative play. Rio Alto has a market cap of less than $300-million. The higher-risk nature of the stock is reflected in the extraordinarily cheap trailing price-to-cash-flow multiple of less than four times and an average analyst target price, at $3.74, more than double the current stock value. Rio Alto appears to have decent upside potential, but volatility is likely and only investors with strong stomachs should commit serious portfolio assets to this one. There are, as always, risks to owning a speculative play like Rio Alto.