A three-dollar bag of heroin, ~1969 NYC, anyway. There were
also the deuce and dime bags
A five-dollar bag of the goods was, for reasons I have never been able
to comprehend, known as a "pound" bag, rarely a "nickel bag," such term being used mainly for weed.
Four and six dollar bags were
called just that, fours
The denomination one found
might well depend
on where in the city you were
. For example, treys were
common all over the LES, while
deuces seemed to prevail in areas of the Bronx.