Just stumbled across this info and thought it to be interesting.
A tonne of ore from a gold mine produces just 5 grams (0.18 ounce) of gold on average, whereas a tonne of discarded mobile phones can yield 150 grams (5.3 ounce) or more, according to a study by Yokohama Metal Co Ltd, another recycling firm.
The same volume of discarded mobile phones also contains around 100 kg (220 lb) of copper and 3 kg (6.6 lb) of silver, among other metals.
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