Maybe brass neck-ring is almost light in your hand (4)
I believe the answer is:
torc
'maybe brass neck-ring' is the definition.
(historical type of neck ornament)
'almost light in your hand' is the wordplay.
'almost' means to remove the last letter (most of the word but not all of it).
'light in your hand' becomes 'torch' (hand-held light).
'torch' with its final letter taken away is 'TORC'.
'is' is the link.
(Other definitions for torc that I've seen before include "Rigid circular necklace" , "Choker" , "One gets into a twist" , "ancient necklace" , "Metal neck ornament of ancient Britons" .)