KORONADAL, Philippines: The rough, juddering road to Tampakan is flanked by languid dogs and animated roosters, modest breeze-block houses and burning coconut husks. Small streams cut the path and signs warn of the risks of landslides in these mountains of upland Mindanao in the Philippines. There are eyes on the road too. Local men in uniforms run security along the ancestral domain now in the hands of a mining company about which little is known. For decades, the promise of mining has hovered...