Case quarter

In the 1980’s in Essex county, Nj, I worked in a restaurant where the wait staff was predominantly white and the dish room was predominantly black. (I maintain I was the last white American man to work as a dishwasher!) whenever any of my coworkers wanted a quarter for change they would always ask for a “case quarter.” No explanation was asked for, none given. But it was fairly widespread urban slang at least in the mid eighties in northern nj. Just now, I’m watching an old film on tcm, “flying down to Rio”, and one of the principle characters asked another for a “case quarter” again looking for a 25 cent piece for smaller change. No further context given. Brings back wonderful memories, as well as a few questions!