In Pulp Fiction, when Vincent buys heroin from Lance, he informs Vincent that he only has baggies to hold his heroin:
I'm outta balloons. Is a baggie all right?
Later, Mia mistakes the heroin for cocaine and immediately over doses.
We see Mia use cocaine in two separate scenes and it is implied that she is a regular user due to the ease and familiarity that she cuts and snorts it...as if she does it all of the time.
How could a regular cocaine user such as Mia not know that she wasn't snorting cocaine? I
I am assuming that heroin is normally stored in balloons due to Lance's earlier dialogue. Mia looked quite excited when she saw the baggie and had no reservations about snorting it.
Did Mia just assume that it was cocaine due to the fact that it was in a baggie rather than a balloon?