Guyana Goldfields (GUYFF) released its Q3 results last week, and the value investors have learned another hard lesson in the mining sector. All-in sustaining costs came in nearly $500/oz above guidance, and the company is tracking for well below its reiterated guidance. As I've discussed in previous articles, there is no sector I'm aware of with similar share price and value destruction, and it is a risky sector to go shopping for value in. Names like Primero (PPPMF), Canaco Resources, Seafield Resources, Allied Nevada Gold, and many others have seen hundred-million