[deted1]

I have a couple of customers with honed black marble in their showers and it holds up ok even with a potassium chloride water softener. They treat the walls like glass and squeegee them after each use. Coincidentally the floors of both showers are slab with four seams from the corners. The floors are treated with slip grip.

Neither shower is enhanced.

They use only liquid soap and never use shower oils. We treat them once per year for some minor etching and other damage and reseal. We have had to redo the grout in the perimeter of the floor in each shower twice in four years.

They used non-sanded dark gray grout. There is some chalking but their housekeeper scrubs it out regularly.

Each shower probably costs the customer $800 per year to maintain.