It does appear when (harmala) EA freezes the EA goes red. So I wonder what reaction is happening there.

When I used already extracted harmala and freeze precipitated it in EA the harmala remained more or less the same color maybe slightly more red?

Anyway my thoughts are and I could be totally wrong, is that it is likely a saturation issue. I would bet R2 is mostly still harmala just with few more impurities. Perhaps the harmala crashes first and impurities don't crash as easily. However, if there's a saturation issue present as well, I would guess harmala crashes first and then impurities and left over harmala remain in the EA.

I base this on absolutely no facts.

Cool looking red crystals though. Sorry Loveall, when you say zinc converted do you mean THH?

I've had success with cleaner harmala simply by using more water in dissolving of citrate step. And I don't wash with ammonia. Although I'm thinking of purifying sudsy ammonia so I can see how clean I can get it in the final step. Sodium carbonate doesn't seem to work the best.

But I love your work with the freeze precipitation. It would be interesting to do a base, pull then freeze run. Just to see what comes out of it. If I have time this week I may give that a quick go.