What you have there are dendrites. They usually form when crystals are grown rapidly, which I see a lot when folks perform evaporative crystallization using heat and vacuum, rather than a slow evaporation done at 1atm and room temperature. If you just plan on milling the growths and rinsing them they are fine, but dendrites are far more likely to have solvent inclusions and are harder to rinse properly. I would reccomend trying to slow your process down, usually with the acetone method that means using some kind of semi-permeable barrier that slows the rate of solvent evaporation.
One photo shows THCA crystallized rapidly in a vacuum oven at 45c and -20mmHg. The other is THCA crystallized more slowly in a fume hood at room temp.
Nice, yeah I’ve just been doing experiments all this is going to get trashed or analyzed after I’m done playing but thanks for the info that is awesome. The next round I put plastic wrap on beaker with rubber band to slow it down to see the other side of the spectrum with really slow growth
Usually I will leave a crystallizing dish open top in a fume hood initially until I see precipitation begin, then put parafilm over the dish and poke a few holes in it.
