My dear friends, let me express my opinion on the subject. Harmaline can be converted to THH using Zinc metal. Harmine can't. For any of you that have some chemical education, you can see that Harmine's double bonds that need to be reduced, are part of a fully aromatic ring. Which gives extra stability to the system thus, making it extremely difficult to be reduced. This is the reason why let's say benzene ring is soo much more difficult to be reduced compared to cyclohexadiene. Now on harmaline, this aromaticity does not exist.
Now the reason that you see the bubbling, is not due to harmine reduction. You see zinc, can reduce a double bond, but it can also reduce the hydrogen ions coming from HCl and convert them to H2. That's the bubbles!! Zinc chloride is the byproduct, which will become visible as a white solid when it exceeds its solubility limit.
Another thing to be noted. I think that harmine and THH are blue under UV. You cannot distinguish them. And I think that harmaline is yellowish-greenish. Don't take my word on that though. I personally believe that the way to go is to separate harmine and harmaline with the known method, and apply the process to the harmaline alone. Then, you get pure THH with a small percentage of unreduced harmine in it.
And now let's speculate. My opinion (and remeber, I do not want to raise any voices around here) is that Flowing Visions do the same thing. There is no organic process here. None. Even in the worst case scenario that they precipitate-separate somehow the THH from Banisteriopsis Caapi, they have to make the HCl salt, right?? Do you really think they do it "Manske" style?? No way...can any of you taste the salty salt contamination that accompanies Manske method??? Also, pure THH hydrochloride HAS a greenish tint which makes a pretty nice camouflage for claiming an all-natural method. I mean, come on, they know their target group!! A "natural extraction method" is a perfect marketing sentence!! And I also believe that Flowing Visions have an account in here!! So please, don't attack meee!! I am only speculating!!
All in all, I think it is EXTREMELY easy to have some THH with the zinc method. And fast also. Giving very high yields. And with rue as the harmaline source?? Seems that we will see a shift in consciousness in the next year

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And if you see a vendor appearing in Europe selling THH, it's me!!! So you better hurry and kick me out of business!!