What did I take on Haloween?

My friend bought 2 grams of a white substance purported to be MDMA. It definitely was not. Nor was it coke, amphetamines, ketamine, or an opiate (I would know). During the come up I felt extremely apathetic and relaxed. The high wasn't unpleasant but not to strong. We snorted a bunch of lines and I felt warm feeling inside, lifted spirits, and I was pretty talkative. I was very in tune with the house music (i.e it fucking rocked more than it would sober) and there was little to no come down.

What the hell did I take?

EDIT: Forgot to mention this huge piece of evidence. It tasted really salty.