Correction, you pinned 1ml of test, and another 1ml of carrier oils. Crashing is an issue of solubility. It's like salt in water, you can dissove salt crystals in water but as you keep adding salt, eventually the water won't be able to take any more and the crystals will just fall to the bottom. For most compounds, solubility is also a function of temperature. If you heat the solution, you'll expand its capacity to dissolve the solid. That's why hair dryers, ovens and boiling water help re-dissolve the crystals. You are increasing the solubility of the oil by heating it up. Crashing is yet another phenomenon. You can make something crash by cooling it, which lowers its solubility until a solid forms. Sometimes it won't re-dissolve even with subsequent re-heating because the precipitated solid triggers re-crystallization of the solid. Basically the solution gets "stuck" as crystals and can't re-dissolve.You can see this in the chemistry lab all the time. You'll have a solution that should be crystalizing, but it stays in solution. If you add a boiling chip, a few crystals of what you're trying to precipitate or even scratch the bottom of the beaker, you can trigger a precipitation and force the entire solution to crash.

He pinned it like that