well, puifying meth is a piece of cake. There are 2 schemes, 1, you put with the meth, something it is immoscible in. Acetone is the popular choiced, the sol. of meth in quality aceton is 1g/100ml, but if you put the acetone in the freezer until it's below 0c, the solubility is more like 0.5g/100ml.. Using 5ml/g, crush it up, add the ice cold acetone, stir it for 2 minutes, let it settle, and decant or seperatory funnel or buchner funnel the acetone off and let it dry/blow a fan on it gently and thats your basic acetone wash, which works great for the most common adulterant, a sulphur compound. Also sugars and fats, acetone is affective on. The opposite also works. Disolve the meth in methanol or isopropyl, and filter it in the buchner funnel and the liquid contains the meth and hopefully some things that didn't dissolve in the alcohol will be filtered out, Then you can concentrate the solvent and leave it to crystallize