Finish is the single largest lever on the wet performance of a paving stone, and it is usually chosen on appearance alone. On Shahabad Grey the spread runs from 42 PTV wet honed to 48 riven and 48 to 52 shot blasted. Bush hammered pushes past 54 but is only appropriate on kerbs and heavily trafficked thresholds.
The trade-off is laying tolerance and cleanability. Riven faces vary in plane by up to 3 mm across a unit, which shows in a tight-jointed commercial layout and makes machine cleaning less effective. Honed faces lay flat and clean easily but need shot blasting or a textured band anywhere a wet fall is likely.
For a mixed scheme the usual resolution is honed as the field with shot blasted at ramps, crossings and external stairs, cut from the same bed so the colour holds. Because the finishing lines and the quarry sit on one site, that split can be produced against one order rather than sourced separately.
Polished finishes have no place outdoors in the UK. At 22 to 26 PTV wet they fail any reasonable access assessment and the surface will dull under grit within a season.
Where a scheme is being audited, ask for the pendulum test on the exact finish being supplied, on a sample from the production batch. A figure from a different finish on the same stone is not transferable.