Apple’s ninth annual Environmental Responsibility Report summarises the company’s work on its three environmental priorities of renewable energy, safer materials & processes and conserving resources. As part of the third of those, the company revealed that its recycling program last year recovered 89 million pounds of materials – Business Insider noting that this included a cool $40M worth of gold.

Gold is commonly used in circuit boards because it has low electrical resistance and, unlike copper, doesn’t corrode. In most applications, a thin layer of gold covers a thicker layer of copper – which was a second valuable material recovered by Apple …

Almost three million pounds of copper was recycled – worth over $6M – along with silver, nickel, aluminum, steel, lead, zinc, tin, cobalt, glass and plastics.

The iPhone recycling robot Apple showed off last month was one of the tools used by the company to recover materials. Fairphone estimates that the average smartphone contains around 30mg of gold.

Apple is also preparing for Earth Day with a campaign raising money for the World Wide Fund for Nature, alongside iPad-based Earth Day lessons for students.

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