What Is This Material?! Rutilated Crystal Inclusions

Hi guys,

I've been banging my head against the wall for a while trying to figure out how to create the kind of inclusions that you see with rutilated crystals.

I tried angelina fiber, which has the right iridescence, but was way too thin and like...floppy?

I found a video where a woman has a pretty decent facsimile, she doesn't carry it for sale anymore and she doesn't say what the material is.

Does anyone have any ideas what this could be, or could you recommend something with a similar look/texture?

I will accept and all suggestions because at this point, I just google whatever comes to my mind. Like fiber optic...strands, hay, straw, flaxen...fiber, stiff plant fiber...thistles....LOL, I have no clue and my mind won't rest.

Thank ya'll in advance!