I was working in a house today where the new owners are just moving in. The wife had a bottle of some type of cleaner, a big rag and a scrub brush and was scrubbing away on the hearth as hard as she could scrub. I commented on how hard she was working and she said there was something all over the hearth she couldn't get off and showed me the rag, which was almost completely rust colored from the scrubbing. I explained the rock on the hearth had some big veins of iron and that was rust she was "cleaning" off the rock. She had been scrubbing for two days. Lol