Some rags woven into a very fine material (8)
I believe the answer is:
gossamer
'fine material' is the definition.
(I've seen this before)
'some rags woven' is the wordplay.
'woven' indicates anagramming the letters.
'some'+'rags'='somerags'
'somerags' with letters rearranged gives 'GOSSAMER'.
'into a very' is the link.
This may not be right. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for gossamer that I've seen before include "Spider-woven threads seen on hedges" , "Some rags (anag.)" , "Filmy floating cobweb" , "Smears go onto light delicate material" , "Material spun by spiders" .)