MSM has a lower melting point than meth by quite a bit. Did you personally make this meth? You need to do a melt test, which you can find a tutorial to in the analytical chemistry forum. I'm sitting on the shitter at 3:47 am, but my recollection is meth melts at 167 (165?)°C if you get a significantly different number something is wrong ( keeping in mind that is a sea level measurement so it will be slightly lower depending on your altitude) edit, I should also mention that acetone is great at removing MSM specifically from meth but doesn't remove much of anything else.