Metal headbanging primarily avoided by Madhuri while dancing (6)

I believe the answer is:

radium

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'metal' is the definition.
(radium is a kind of metal)

I can't explain the remainder of the clue.

(Other definitions for radium that I've seen before include "Chemical element, Ra" , "Ra (atomic number 88)" , "Radioactive metallic element found in pitchblende" , "Radioactive element discovered by the Curies" , "Radioactive metal" .)

I've seen this clue in The Hindu.

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