Like the optimum, so return the fireproof mineral (8)

I believe the answer is:

asbestos

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'fireproof mineral' is the definition.
'asbestos' can be an answer for 'mineral' (asbestos is a kind of mineral). I'm unsure of the 'fireproof' bit.

'like the optimum so return' is the wordplay.
'like' becomes 'as'.
'the optimum' becomes 'best' (I've seen this before).
'return' shows that the letters should be reversed in order.
'so' back-to-front is 'os'.
'as'+'best'+'os'='ASBESTOS'

'the' acts as a link.

Can you help me to learn more?

(Other definitions for asbestos that I've seen before include "Protective fabric" , "Fire-resistant material, a danger to health" , "I might end up lagging" , "Fire-resistant material, injurious to health" , "'Fireproof substance, dangerous to health (8)'" .)

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

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