Shed tears and stop short – is that clear? (7)
I believe the answer is:
'that clear?' is the definition.
(as in 'crystal clear')
'shed tears and stop short' is the wordplay.
'shed tears' becomes 'cry' (to cry is to shed tears).
'and' means one lot of letters go next to another.
'stop' becomes 'stall' (stalling is a kind of stopping).
'short' means to remove the last letter.
'stall' with its final letter taken off is 'stal'.
'is' acts as a link.
(Other definitions for crystal that I've seen before include "Highly-transparent glass" , "Quality glass" , "Quartz, for example" , "Glassware" , "The fortune teller may use a . . . . . . . ball" .)