During archaeological work, nothing's in the shade (6)
I believe the answer is:
indigo
'the shade' is the definition.
(shade of blue)
'during archaeological work nothing's' is the wordplay.
'during' becomes 'in' (e.g. during February means in February).
'archaeological work' becomes 'dig'.
'nothing' becomes 'o' (O resembles 0).
'in'+'dig'+'o'='INDIGO'
'in' is the link.
(Other definitions for indigo that I've seen before include "Tropical plant" , "One of the colours of the rainbow" , "Deep dark blue" , "type of dye" , "Colour - I'd go in (anag)" .)