Roughly prepares pitches for paving materials (12)

I believe the answer is:

cobblestones

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'paving materials' is the definition.
The definition and answer can be both man-made objects as well as being plural nouns.
Maybe they are linked in a way I don't understand?

'roughly prepares pitches' is the wordplay.
'roughly prepares' becomes 'cobbles' (as in cobbling something together).
'pitches' becomes 'tones' (tone is a kind of pitch).
'cobbles'+'tones'='COBBLESTONES'

'for' is the link.

Can you help me to learn more?

(Another definition for cobblestones that I've seen is " They made way".)

I've seen this clue in The Guardian.

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