Crack Cocaine is a smokeable version of cocaine. They called it crack cocaine due to the crackling sound it made when it was smoked. In 1985 crack cocaine started to appear in large cities such as Miami, Los Angeles and Chicago. There was a crack epidemic that happened between the years of 1984 to 1990. It was easy for crack to spread like a wildfire due the price. The price of powdered cocaine was significantly more expensive than its counterpart crack. Crack was more affordable to common middle class people. Here is a documentary
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