How can natural - stone stair treads be made durable?

Natural granite or marble stairs are very common products. They are indispensable for stair treads in home decoration, hotels, airports, subways, and high-speed railway stations. We often use some black granite and white marble to make the treads and risers of the stairs. These natural stones are sturdy and durable, and can also enhance the grade of the building. However, since there are many people walking on them, the steps and risers need to be sturdy to ensure that they will not be broken or fractured during use and to guarantee safety. Nevertheless, it is not difficult for us to find that due to unreasonable designs, the stair treads are prone to breakage, which affects both their appearance and safety.

To prevent the occurrence of chipping and corner-breaking phenomena on the stair treads, the following six points should be noted during the design:
(1) The depth of the grooves on the stair treads should not be greater than 2 mm.
(2) The spacing between the grooves on the stair treads should be greater than 10 mm.
(3) The overhanging length of the front end of the stair tread panel should not exceed 5 mm beyond the riser.
(4) The distance between the first groove on the stair tread and the front end of the stair tread is preferably greater than 20 mm.
(5) The number of grooves on the stair tread should not exceed five.
(6) The thickness of the stair tread stone should be greater than 20 mm.