starting maybe 20 minutes ago, i took my vaporgenie, 8 stainless steel meshes, a pinch of indica, and sat down. Waiting on milligram scale to arrive. razored off a crystal heap maybe size of small pea, razored it in half, took took most of remaining and sprinkled on top of 8 stainless steel mesh and under a light covering of indica. Quite nervous, regardless of extensive psychedelic experience including a lot of salvia, put some shpongle on. did deep breathing. heart beat shallow, weak, a bit rapid. Took one long slow hit. put lighter down. felt something within a couple of seconds, heart became steady and strong, still a bit rapid. Felt calmness and confidence descend on me in a heated slow wave. Very warm sensation slowly heated me. felt relaxed. face flushed with warmth. Then maybe 5 minutes later repeated same hit. Basically a lighter repeat of/continuation of same feeling. Wasnt scared anymore. didnt taste anything unusual except the flavor of weed. Felt odd. Possibly very most faintest cev closed spindle of millions of purple violet blue sparkles in dense patterned grouping. faint ghosts of other undefined possible cev. Warmth has a three dimensional feel to it. A bit of a rising sensation. Felt confident and good. Dont know if this was a threshold DMT, or just the weed. Weed doesnt usually hit me in seconds, but didnt taste chemically taste. Dont know. Am waiting for scale to do an official try, plus I dont know how often I can do this stuff. Think I remember rapid tolerance builds, personal experience has taught me not to do psychedelics more than once a week, so probably use those two hits of miniscule amount only, tonite. Still volcanic feeling, my one successful ayahuasca trip also volcanicly heated, salvia also. Dont know...

From Strassman's research they found no tolerance from IV DMT as far as I can remember.
Also about 10-12mg can be a small as 2 or 3 grains of sea salt.