"Raffi Stepanian is a self-described urban prospector. Stepanian makes his living on his hands and knees, sifting through New York’s dirt, grime and silt to find tiny jewelry fragments hidden in the sidewalks and gutters of the city’s Diamond District."
Mr. Stepanian is pretty unpopular with the local business men probably because they don’t want it to get out that that they drop precious stones and gold all over 47th street
http://www.marketplace.org/topics/life/news-brief/meet-new-yorks-urban-prospector