I'm looking for some insight/critiquing on something I've done...

I followed BLAB tek up to the part pouring off D-limonene from crashed out DMT fumarate, but after that, I tried something that's not in the tek: I added 40mL water to the jar with fumarate and remaining D-limonene, made sure it all dissolved, and then poured the liquid back into 50mL graduated cylinder (see picture). You can see the limo maxed out how much water it would dissolve with and separated on the top, and I decanted this, leaving behind the non-limo solution with water and DMT fumarate, and then evaporated the two separately.

Since my goal was to remove the D-limonene from my final product, I was very happy with appearance of results (picture with 1.7grams), and did bioassay last night with wonderful experience with 55mg. The evaporated part containing D-limonene was a dark gooey mess, and weighed only about 15% of the sum.

OK so far so good, but then I tried to repeat this with larger amount of fumarate, but diluting with more water. I used two 50mL graduated cylinders, pulled limo off the top of one like in picture, and transferred to other with 45mL clean water, and then poured fumarate saturated water from first cylinder into evaporation dish. I repeated this few times until there was about 200mL of water and fumarate in dish, and the water and limo in graduated cylinder looked much clearer. Since it was such a large volume of water to evaporate, it spent a lot of time in dehydrator set at 165°F before it got close to being dry, and then I put on hot plate @ 95°C until it got crumbly dry. Reference picture with 9.6 grams.

My questions is: Why did the first batch come out looking so good and homogenous/waxy/crystally, and second batch is powdery? Second batch also has considerably stronger scent of freebase DMT, granted it's over 5x the weight of first batch, but my gut tells me something with the extra water and/or extra time with heat and exposure to air broke away fumaric acid from DMT freebase. If there is loose freebase DMT and loose fumaric acid, if I simply dissolve into acetone for a bit, should I get 100% DMT fumarate in the end (if I'm even right about loose freebase and fumaric acid)?

Anyone care to share some expertise or conjecture? Please!? This was my first time making DMT fumarate, so I don't have green thumb with this yet, not really sure what I'm dealing with. FWIW, I used reverse osmosis (RO) water... trusting that it's pure, but maybe there's a problem with it?

You should be able to rinse a fair amount of the limonene odour away by using anhydrous acetone. This will dissolve the terpenes and terpenoids while leaving the fumarate untouched. Limonene slowly oxidises in air to a variety of side products, some of which seem to be 'sticky' or to have a surfactant-like action. This is part of the reason why I gave up on limonene.

The "DMT smell" is not in fact DMT freebase but rather indole and skatole that have been formed during a slight decomposition of the DMT. Perhaps limonene or its oxidation byproducts contribute to this decomposition. The starting point will be the absorption of a molecule of atmospheric oxygen to form a peroxide, which might conceivably react with nearby DMT to cleave off the ethylamine sidechain.

The difference in consistency might be down to the larger amount evaporating differently, and also the larger amount of impurities that have come along with it. I wonder if it would crystallise from water better after an acetone wash.

In my case, there is no limonene odor, since I over saturated with H20 and decanted the limo away a few times. It just has that decomposing DMT scent (that I've become extremely fond of).

This is valuable info! Is there any reason I can't substitute D-limonene with Xylene in BLAB tek, assuming I fully evaporate/wash since it's not food safe?

I'll try acetone wash after I'm confident the powder is devoid of all moisture, then see if it'll crystalize in water.

Xylene and limonene are pretty much interchangeable there, notwithstanding food grade considerations - but you have that covered with the acetone wash and water re-x.