Don't know if this helps you know, but I just finished harvesting seeds from some 20 plants -- and it ain't much!

It's not the papery husk with a spine running down the middle -- that would be too easy!

They are grey, rectangular seeds; small, but they have some body to them, unlike the chaff.

There don't seem to be very many seeds, and many flower heads don't have any at all.

Yes,inside the dry papery seedpod you will find little blackish tan nuggets and each one has a few little points at one end.These are heavier and if you put them on a paper plate you can blow lightly on them and the chafe will move to the side of the plate leaving the seeds very noticable.