What is it? You don't mean epsom salts (Magnesium Sulfate) do you? You wouldn't get high but you'd take an epic shit.
Lol its prolly meph, or some other cathinone, effects are said to be similar to MDMA, but I would advise against the use of cathinones, this is entirely my opinion though, and many people on this forum would disagree. IMO if you want to feel like your on MDMA, take MDMA.
If you belive this report then Ivory Wave from 2009 had MDPV in it and got some folks in trouble: http://www.guardian.co.uk/society/2010/aug/17/ivory-wave-drug-alleged-death
I tried it and it is okay, but Blue Silk, while very similar, is a whole lot better. I was never troubled by hallucinations with either of them. I just hope they remain legal in the U.S.