Turns out there are also tiny ziplock bags sized to hold dime sized coins that collectors use.
So it seems like “dime-sized” bag could mean several things:
A bag that’s literally the size of a dime.
A tiny bag for holding a dime-sized coin.
A small bag that would hold a “dime” of cocaine — i.e. $10 worth (which would be a very small amount)
A smallish bag the size of what in drug slang is most commonly called a “dime bag”, which is $10 worth of marijuana, which is substantially more than $10 worth of cocaine.
Yep, right on the money. But back in the day we used paper bindles like this...
https://www.foodforestgarden.org/wp-content/uploads/2013/01/how_to_fold_a_bindle.pdf
A dime bag of drugs always means $10 worth no matter what it is. Yes, bag size can change. In the early 70s a dime bag of weed was a 1/4 ounce bag. That would be about 1/4 of a ziplock sandwich bag.