Of course, if we take a commodity such as I'm holding in my hand right now, glass—and you can't see it—it's a completely inert substance composed of sand and soda ash, two materials that the world is clearly not short of. If it is put into a landfill, there is no leachate from glass and it happens to be a material that's very difficult to recycle. It's heavy and it costs a lot of energy to move around.
Mr. Nickel, what's your answer for glass?