Pharaoh stuck with heart of flint (4)

I believe the answer is:

seti

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'pharaoh' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'stuck with heart of flint' is the wordplay.
'stuck' becomes 'set' (I've seen this in another clue).
'with' means one lot of letters go next to another.
'heart of' says to take the centre.
The middle of 'flint' is 'i'.
'set'+'i'='SETI'

Can you help me to learn more?

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

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