Basin contains pound of black liquid (5,3)

I believe the answer is:

squid ink

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'black liquid' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'basin contains pound' is the wordplay.
'basin' becomes 'sink' (I've seen this before).
'contains' indicates putting letters inside.
'pound' becomes 'quid' (UK slang for a pound).
'sink' enclosing 'quid' is 'SQUID INK'.

'of' acts as a link.

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I've seen this clue in the Sydney Morning Herald.

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