Shortage of diamonds on ground (6)
I believe the answer is:
dearth
'shortage' is the definition.
('dearth' can be a synonym of 'shortage')
'diamonds on ground' is the wordplay.
'diamonds' becomes 'd' (abbreviation in bridge say).
'on' is a charade indicator (letters next to each other).
'ground' becomes 'earth' ('earth' can be a synonym of 'ground').
'd'+'earth'='DEARTH'
'of' acts as a link.
(Other definitions for dearth that I've seen before include "Shortage, paucity" , "Scarcity of thread" , "want" , "Scarcity, paucity" , "Shortage, lack" .)