This might be unnecessarily pedantic, but is there some reasoning behind which small stones are used (along with bricks and concrete) to make the various stone paths? For instance, granite stone road requires softer sedimentary small stones to be used in construction, but can also be made with basalt, Or how claystone road requires mostly hard igneous or metamorphic small stones but also has halite and limestone on the list?
I don't know anything about road construction, so this was mostly just confusing for me.