Now that I know the cause of the problem and how to prevent it, I am willing to leave things as they are. The build-up is rather mild at the moment, and unless it gets worse, I see no reason to try anything potentially harmful.
Take a look:
I first noticed it a few months ago, and it has been getting worse. Is this just mineral deposits? If so, how do I get rid of it? I've heard white vinegar, but not only is this my favorite and most used pot, it is the most expensive. I want to be very sure that whatever I do will not harm it. If it isn't mineral deposits, any ideas? Your feedback would be appreciated.(Edit) More information: Yes, the pot is porous. I use spring water to make tea, but I rinse my pots with tap water. Its this teapot right here.