Due to exceptional kindness of Ondra Novák, I acquired some microscopic photos of molds (white spots on wetter tea and aspergillus crystatum from Fu brick). Actually, I wanted to post the photos of the former (the white spots) to back up my earlier statement that it is mold (and to refute the statement of certain other people). Some photos were composed from Z-stacks using Combine ZP, if you're interested in the source photos, just ask me - but the depth of field is really small so one does not see that much from that.
White spots first:
Unfortunately, I drank almost all of tea with coating I had, therefore I had to use a tea which has been only mildly wet stored and had only a couple of white spots. The magnification is a bit limited by the dry objective used, but it should be sufficient nevertheless:
... and a closeup
The only other thing that the white spots could have been was probably crystals of minerals (sort of like efflorescence) - and the white matter is obviously not crystals (at this magnification level, they would be entirely obvious). It totally looks like puffs of mold hyphae.
I wonder what sort of mold it is. It might be some acremonium, maybe (which also plays its role in shu puerh). Anyway, I'm currently searching for a lab which could perform the analysis.
How does our good friend, found, e.g., in Fu bricks, look like?
The microworld is entirely amazing - is it not?