Later step made a lot of gunpowder (9)

I believe the answer is:

saltpetre

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'a lot of gunpowder' is the definition.
I can't tell whether this definition defines the answer.

'later step made' is the wordplay.
'made' is an anagram indicator.
'later'+'step'='laterstep'
'laterstep' with letters rearranged gives 'SALTPETRE'.

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(Other definitions for saltpetre that I've seen before include "Gunpowder ingredient" , "Component of gunpowder" , "Constituent of gunpowder" , "Nitre" , "Explosive ingredient" .)

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

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