The Art of the Potentially Deadly Deal: Marketing Heroin on the Street
The empty glassine packets can be found in Manhattan, Brooklyn and beyond, scattered on streets and sidewalks with only obscure slogans or graphic images to suggest their former use. At one time they contained heroin and the markings stamped on the packets were meant to differentiate strains of varying purity or provenance. http://www.nytimes.com/2010/06/23/arts/design/23heroin.html

