The most common and most likely answer to this crossword clue is the 5 letter word LUREX
L
U
R
E
X
Buddy explains!

The straight part
We know that "shiny fabric" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case shiny fabric = lurex.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does LUREX mean?
LUREX noun- A form of yarn (or fabric made from it) that incorporates a glittering metallic thread.