How do you properly clean a brass mortar and pestle?

Is it normal for stone sediment to appear in a Pestle and Mortar set?

• I've never owned one before, but we just got a granite one and noticed it has a thin powder (or stone sediment) around the bowl and pestle bottom. I've washed it but some remains and I'm concerned it will end up in the food I make. I think it's coming off the stone the pestle and mortar is made of. Is this normal?

• Answer:

  If you've washed it, you have removed any powdered stone that might be there. The surface is rough because otherwise the thing won't work and and that rough surface is always going to appear "powdery" no matter how clean it is. Don't scrub the heck out of it, either. I scrubbed a mortar and pestle of mine too hard with a green scrub pad and I must have polished it a bit too much because it doesn't work as well as it did.