If you take a look at Apple's Environment page you might well be impressed by the amount of reuse Apple is getting by taking back devices. The numbers look great: What's weird about these numbers is that they are round numbers. In fact they are very simple, round numbers. You just have to be using the right units. Just look at that... 2,204 lbs of gold. But wait! Isn't 1kg roughly 2.204 lbs? (Why, yes. It's 2.20462 lbs). So, sounds like Apple recovered 1,000 kg of gold. Now take a look at tin... 4,408 lbs... 2,000 kg. And silver... 6,612 lbs... 3,000 kg. And lead... 44,080 lbs... 20,000 kg. Here are the figures above converted to kg using 1 kg = 2.204 lbs. Steel 28,101,000 lbs = 12,750,000 kg Plastics 13,422,360 lbs = 6,090,000 kg Glass 11,945,680 lbs = 5,420,000 kg Aluminum 4,518,200 lbs = 2,050,000 kg Copper 2,953,360 lbs = 1,340,000 kg Cobalt 189,544 lbs = 86,000 kg Zinc 130,036 lbs = 59,000 kg Lead 44,080 lbs = 20,000 kg