Own costly treasure (4,4)

I believe the answer is:

hold dear

'treasure' is the definition.
(synonyms)

'own costly' is the wordplay.
'own' becomes 'hold' (I've seen this in another clue).
'costly' becomes 'dear' (synonyms).
'hold'+'dear'='HOLD DEAR'

I've seen this clue in The Telegraph.

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