A Shahabad specification fails in the same three places every time: an unstated finish, an unstated calibration tolerance, and a slip target written against the wrong face. All three are avoidable at drawing stage.
Name the finish against the face, not the product. Riven, honed, brushed and polished are four different materials in performance terms even when they come off the same block. The riven face on Shahabad Grey returns 59 PTV wet; the honed face on the same bed returns 36. If the schedule says 'natural finish' the yard will send whatever the last order took.
Calibration is the second gap. We work to ±1 mm on honed and brushed material at 20, 25 and 30 mm, and ±3 mm on riven where the cleft governs. Write the tolerance into the schedule if the tiler is laying on a fixed bed depth.
Third, state the bed depth you want quoted. Moving from 20 mm to 30 mm on a 400 m² terrace adds roughly 6.4 tonnes and changes the crate count, which changes the freight line rather than the stone line.
Everything else — jointing, movement joints, sealing — follows normal limestone practice. The stone is dense, the absorption is under half a percent, and it behaves predictably once the specification is complete.