Spoils sought by antiquarians (5)
I believe the answer is:
ruins
'spoils' is the definition.
(ruining is a kind of spoiling)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for ruins that I've seen before include "Broken-down remnants" , "Wrecks" , "Rubble" , "Collapsed, disintegrated buildings" , "Damages irreparably" .)