The Shave Den's M-Bomb

[henkverhaar]

Whatever - it may be heat and they melt - but they are used in solid anhydrous balms (no alcohol either) and they combine without causing any lumps/grittiness crystals reforming in the balm - I'll obtain an example an send it to you.

Correct. The normal way of doing that is mechanically. Menthol crystals can be ground to a very fine slurry in an oil mull. These crystals are dispersed in the 'anhydrous emulsion' (actually a suspension) and since no dissolution in oil takes place in the first place, will not recrystallize.