I am leaving a building, walking towards the door; it seems to be some sort of school. See an envelope on a table near door and it seems to have stamps inside, so I pick up to examine. A stamp collector I know, Gus, walks over and takes it from me. He pulls out stamps and they are all good items. He walks away with the envelope, saying it was his and he had lost it. Walking out double glass doors, I see on steps some UN stamps laid out on a black paper. All are used and sloppily mounted. I stop and pick up the only possible item of valuable content, a special UN souvenir sheet. It looks okay, but when I turn it over, it has tiny round perforations on back forming small stamp-like rectangles. All of which ruins its value.