The donkey call around the craft is harsh and metallic (6)
I believe the answer is:
brassy
'harsh and metallic' is the definition.
(I've seen this in another clue)
'the donkey call around the craft' is the wordplay.
'the donkey call' becomes 'bray' (I've seen this before).
'around' indicates putting letters inside.
'the craft' becomes 'SS' (prefix in ship names eg SS Great Britain).
'bray' placed around 'ss' is 'BRASSY'.
'is' acts as a link.
(Other definitions for brassy that I've seen before include "Sounding like cornet maybe" , "Showy - harsh" , "Tastelessly showy, loud" , "are showing cheek?" , "Gaudy" .)