Old baronet collects planes and diamonds, lovely things (6,4)
I believe the answer is:
objets dart
'things' is the definition.
(I have seen 'decorative things' mean 'objets dart' so perhaps 'things' could also mean 'objets dart')
'old baronet collects planes and diamonds lovely' is the wordplay.
I cannot really see how this works, but
'old' could be 'o' (abbreviation) and 'o' is located in the answer.
'planes' could be 'jets' (jet is a kind of plane) and 'jets' is found within the answer.
'diamonds' could be 'd' (abbreviation in bridge say) and 'd' is located in the answer.
'baronet' could be 'bart' (synonyms) and 'bart' is located in the remaining letters.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for objets dart that I've seen before include "decorative things" , "decorative little items" , "collectible items" , "Small decorative items" .)