Okay i was reading another thread here titled Naptha and Residue and was thinking perhaps i should start a thread(and this may be worth stickying) on this.

What naptha to use and what not to use.

Il start it off with 2 brands 1 good and 1 im unsure of.

Neon brand states its just Petrolium distilate / naptha and it smells like naptha should - evaps cleanly.

Newport lighter fluid states its petrolium spirit and works like naptha should but it doesnt smell like naptha at all. Swim doesnt like or trust it.

depends on the method you wish to use

light aliphatic naptha (like VM&P), is good for recrystallization, though dmt has marginal solubility (better when warm); because of this, it's used to freeze precipitate the final product.

aromatic [medium-heavy weight] naptha (has a mix of xylene,toluene, and perhaps some benzene) is fine for the extraction, but not easily evaporated and not as effective for freeze precipitation

the former is more commonly used

hrmm perhaps that is why the smell is different on those 2 then.
another difference i have noted on those two is the clouding - with the neon it clouds fast on evap and drops out xtals fast on the freeze precip - it even clouds when you blow on it when it is almost ready for freeze precipping.
the other listed brand doesnt do so - and thinking about it now swim says it evaps slower.

Ronsonol Lighter Fuel seems to work quite well for freeze-precipitation although SWIM doesn't have anything to compare it with. The bottle says "Naphtha, CAS # 64742-89-8" and "Contains Light and Medium Aliphatic Naphtha."

My imaginary friend told me the following:

Ace VM&P Naptha = Does not evap cleanly (Oily reside)
Klean Strip VM&P Naptha = Does not evap cleanly (more Oily residue)
Bestine Solvent & Thinner (n-Heptane) = Evaps mostly cleanly at room temp (a hardly detectable amount of residue), if a fan is used, there is more of something left, but still it is very hard to detect. My IF suspects that if this evap was performed under reduced pressure, that nothing would be left. Unfortunately my IF lives in a parallel universe in which devices to reduce air pressure do not exist.

I have a FOAF, that lives in yet another dimension, that was able to obtain ACS Reagent grade petroleum ether, that evaps cleanly in a matter of minutes.

SWIM has never had any problems with VM&P naptha. It always evaps cleanly.