When doing a STB my first pull is always pure white, the second with a yellow tint, third yellow and so on until it's just yellow oil. The only thing I can think of is the plant material gradually breaking down and releasing fats. Why would the first pull not have any yellow? I get that the last pull has no crystal to hold so there is no white but why the gradual yellowing? Is it plant fats being slowly released?

Also, is it still uncertain as to whether yellow dmt has different effects than white? If so, how would you describe the differences?

I'm fairly certain that you are right on the money with the plant fats. I tried doing a STB with MHRB one time and will never do it again. Even comparing it to the A/B I did with only one defatting wash, it was fairly dirty. There was a yellow funk that that took 3x re-x to eliminate.

I believe that the reason the first pull comes out white is because the freebase DMT is more soluble in your solvent than the plant fats and whatever else is in the yellow funk. As the DMT concentration goes down, some of the less soluble things are able to migrate over with it. I used naphtha for my STB and the first pull was definitely not white but still much lighter than subsequent pulls.

Alright sounds good. I may toy around with different extractin teks and see which do what. Now that I have an understanding of the basics I think it may be time to move along and see what else is out there. So far the yellowing doesn't seem to be inhibiting activity, I will say that. Thanks.