Returning a little sexy nod, rascal produces gemstone (8)
I believe the answer is:
sardonyx
'gemstone' is the definition.
(sardonyx is a kind of gemstone)
'returning a little sexy nod rascal' is the wordplay.
'returning' is a reversal indicator.
'a little' indicates a hidden word (a little bit of the clue).
'xynodras' can be found hidden inside 'sexy nod rascal'.
'xynodras' backwards is 'SARDONYX'.
'produces' acts as a link.
(Other definitions for sardonyx that I've seen before include "A stone; dry Saxon (anag.)" , "Semi-precious stone" , "Mineral" .)