Crossword Genius

Mine Korea for porphyry? (3)

Ross

I believe the answer is:

ore

I'm a little stuck... Click here to teach me more about this clue!

'porphyry?' is the definition.
The definition and answer can be both substances as well as being singular nouns.
Perhaps you can see an association between them that I can't see?

'mine korea' is the wordplay.
'ORE' is hidden within the letters.
However, I'm uncertain how this is indicated.

'for' acts as a link.

Can you help me to learn more?

(Other definitions for ore that I've seen before include "Valuable resource" , "Solid rock containing metal" , "tangle" , "Raw mineral" , "not worth a lot to Danes" .)

I've seen this clue in The Independent.
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