Thanks for the response. I'm right now searching the net for pictures
of all the things that you mentioned. So far the closest match for
the "stars" are trichomes. One thing that doesn't exactly match is
that the internal structure looks very different from that of
trichomes. But the shape is exactly right.

Can there be that many trichomes in the air that they become the
dominating thing? (On my samples I have more trichomes than any other
thing, except something that looks like mineral dust grains.)

Thanks,

- Alex