Crossword Genius

One offering bids for coal after breaking rocks (5,9)

Ross

I believe the answer is:

blood sacrifice

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'one' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'bids for coal after breaking rocks' is the wordplay.
'after breaking' is an anagram indicator.
'rocks' becomes 'ice' (both can informally mean diamonds).
'bids'+'for'+'coal'='bidsforcoal'
'bidsforcoal' with letters rearranged gives 'bloodsacrif'.
'bloodsacrif'+'ice'='BLOOD-SACRIFICE'

'offering' is the link.

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I've seen this clue in The Times and The Sunday Times.
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