There have been a lot of differing reports about the characteristics of different batches of a-PVP going around, and it seems to me that both forms (hydrochloride and freebase) are currently being sold by vendors. The hydrochloride salt is apparently difficult but not impossible to vaporize, has a fairly high melting point, produces harsh vapors, and is somewhat less potent, due at least in part to the added mass of the HCl molecule. The freebase form is very easy to vaporize, and will actually bubble when heated, since it doesn't have the high boiling point that is characteristic of salts. Also, the freebase form tends to remain a viscous liquid after it cools down, whereas hydrochloride salts will solidify. Freebase vapors can form crystalline patterns, but they don't look anything like the crystals that form from hydrochloride vapors.
Per unit mass, the freebase form is more effective, but do be warned, the difference between the two forms is like the difference between crack and powder cocaine.
Per unit mass, the freebase form is more effective, but do be warned, the difference between the two forms is like the difference between crack and powder cocaine.
