Cyclone had disturbed rock (10)

I believe the answer is:

chalcedony

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'rock' is the definition.
The definition and answer can be both substances as well as being singular nouns.
Perhaps they are linked in a way I don't understand?

'cyclone had disturbed' is the wordplay.
'disturbed' is an anagram indicator (the order of letters is disturbed).
'cyclone'+'had'='cyclonehad'
'cyclonehad' with letters rearranged gives 'CHALCEDONY'.

Can you help me to learn more?

(Other definitions for chalcedony that I've seen before include "Gem" , "mineral" .)

I've seen this clue in The Guardian.

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