A slang term for a solid block of cocaine, often mistaken for salt. It is highly dangerous among daily use, because many kids with severe mental issues mistake it for salt.
Ex) The mentally challenged child who had a learning disability fucked up his brain by hitting a line of rocksalt.
Coined by a local hobo overheard during WABC7NY coverage of the 1993 failure of the Sonic the Hedgehog Macy's Thanksgiving Day Parade balloon, this appears to be a term related to what the man was smoking out of his crystal meth pipe when he saw the balloon deflate.
"Jeepers creepers! I gotta stop blazing this Coney Island Rock Salt! It looks like that big fucking balloon is coming right towards me!"