All That Glitters? 5 Ways to Look Closer at Gold

"In large scale mechanized mining, there is often little regard for the environment. The danger to biodiversity begins when roads are built for purposes of exploration and as land is cleared for settlement. The ongoing operations of large scale mechanized mining are also terribly destructive both to the land and to adjacent aquatic ecosystems. And all too often, the spoils of the process continue to poison the environment long after commercial operations have ceased."

However, they explain, small scale miners around the world also utilize "excavation and extraction techniques which are harmful both to themselves and to the environment." For example, cyanide and mercury are used to separate gold from rock: "The cyanide and mercury are frequently dispersed into the environment, and the toxic mercury is very often inhaled by the miners."

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