Enormous assets not declared? (6,6)

I believe the answer is:

untold wealth

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'not declared?' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'enormous assets' is the wordplay.
'enormous' becomes 'untold' (I've seen this before).
'assets' becomes 'wealth' (I've seen this before).
'untold'+'wealth'='UNTOLD WEALTH'

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I've seen this clue in The Globe and Mail.

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