Dug up some fabric (5)
I believe the answer is:
denim
'some fabric' is the definition.
(denim is a kind of fabric)
'dug up' is the wordplay.
'dug' becomes 'mined' (dug into the ground).
'up' is a reversal indicator (in down clue: letters go upwards).
'mined' reversed gives 'DENIM'.
(Other definitions for denim that I've seen before include "Twill cloth" , "Fabric used for jeans" , "Mined badly for a hard-wearing fabric" , "Mined (anag)" , "Coloured cotton twill" .)