How does coarser grain size generally affect a rock's resistance to weathering?

Answer

It tends to increase resistance compared to finer-grained rocks by offering less surface area for reactions.

Coarser-grained rocks, such as sandstone compared to shale, present a smaller relative surface area for a given volume, which generally increases their resistance to weathering processes.

How does coarser grain size generally affect a rock's resistance to weathering?
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