. Marble is softer than Granite and a different make up of minerals. Granite is harder and will degrade in less time than Marble. Both will hold a stain as they are naturally semi porous materials. Acid in OJ will eat at both, so chin pee may eat at them too. But, it would probably take many many years to really affect them much. If you want to sanitize the chiller scrub it down with hot water and toss it in the dish washer no soap. I use peroxide on mine before the dishwasher steam also. They are rocks so do let them cool off before stowing them in the ice chest or they will crack. Don't know if you ever split soft ball size rocks as a kid by heating in the oven and cooling in the freezer but you can do it. It doesn't take nearly as much effort with thin slices of marble or granite.
