'DMT samples were
prepared following extraction from Mimosa tenuiflora inner barks or by laboratory synthesis and then its crystals were recrystallized from solutions of the alkaloid using either hexane or acetonitrile. Irrespective of source, crystals originating from synthesis were predominantly white crystals obtained using crystallization from hexane, whereas yellow samples following recrystallization with acetonitrile. Irrespective of source or solvent, two polymorphs appeared to exist with melting points, determined by DSC, of 57°C to 58 °C for Form I and 45 °C to 46 °C for Form II. Estimates for their enthalpies were 91.9 ± 2.4 J g−1 for Form I and 98.3 ± 2.8 J g−1 for Form II. Form II converted to Form I during DSC; conversion was thus prevented by fast scanning rates of 100 °C min−1. A transition temperature (Tg) in the range −21 °C (2 °C min−1) to −13 °C (100 °C min−1) was determined depending on DSC scanning rate. Its closeness to the melting point indicates a tendency of Form II to convert to Form I on storage, a phenomenon that was also facilitated by grinding. This study indicates that the presence of differently colored DMT free base crystals obtained from recrystallization might also point towards the existence of polymorphs rather than just the presence of impurities.'


All this seems to really say is that acetonitrile gives you yellow spice if you try to recrystalize with it, and that these polymorphs are present in whatever solvent you use. It mentions DMT becoming yellow over time, something we all knew anyway. This piece of info does not even seem to suggest that the solvents themselves affect polymorphism. All it seems to be saying is that one polymorph can become another. It says it suggests that the presence of colour could be due to polymorphism, but the only example it gives of a colour change was in a different solvent which was always yellow, even though it too had different polymorphs just like hexane did. If it has the same polymorphs but both are yellow, and the other solvent gave different polymorphs and they were clear, then how does this suggest polymorphs affect colour? It sounds like it's saying the exact opposite. And which spice did they re-x in acetonitrile, the extracted stuff or the synthetic stuff or both ? What colour was each to begin with ?

Thankyou, that's what I've been trying to get across. That while there exists a polymorphic variant there's nothing to indicate it has anything to do with color. They didn't specify method of crystallization. They also couldn't distinguish the source of the sample DMT, which can be problematic since synthetic DMT can be extracted from the reaction solution with an impurity inseparable with crystallization. These impurities have a significantly higher boiling/melting point than DMT.

The article also mentions that the yellow polymorph reverts to the form of the white polymorph under storage but doesn't detail anything beyond that. One could take from this that again the polymorph only exists as a liquid or vapor but again that's speculation.

People are taking too much from these detail lacking reports as an absolute fact. Sofar all we know is there is a polymorph, and nothing else.

Also with such a miniscule difference in mp between 'form I' and 'form II', could partial pressure play an influential role in the mp/bp of these compounds? I don't see any spectra/chromatagrams in any of these studies to provide a composition list of what was found in the DMT. 

My logic is: We have known impurities that influence crystal coloration and can be hard to separate. We've also observed different melting/boiling points of DMT with no real testing included to determine makeup/purity. Yet through some form of mental gymnastics we're assuming that a wild polymorph suddenly appeared and that has everything to do with crystal coloration and operator error has no role to play. (said operator has no clue where the dmt even came from in some cases, so isolation is moot)

Perhaps there is some very thorough confirmed scientific data I'm just not seeing. I believe myself to be "on mark" however.

On one note I'm lenient toward white/clear spice being 'the more pure' spice. Since we can in a reasonable fashion conclude that colored impurities such as oxide/nmt aren't present. NaOH shouldn't be a concern with proper cleanup toward the end of the extraction. (NaOH most likely won't be white since it'll be accompanied with black basic soup, yet people never fail to amaze..)

I personally favor transparent needlepoint shards. Not the urchin like clusters, but individual needles.