arcticfox wrote:I tried the baking soda today, and it worked like a charm. Just gentle rubbing with my fingers took off all the stains.
I haven't heard of cultivating a patina on teaware other than zi sha clay. Is this a common thing? Does it actually add anything to the tea?
Accumulated scale on clay kettles can be very beautiful. Hagi turns over time very nice, when tea perforates the clay, and the whole piece changes with the crackles getting more visible. Also Shigaraki turns more beautiful the more you use it. Many Japanese unglazed pots also turn more dark and shiny with use.
On porcelain cups or plates i usually clean them with hot water right after drinking, and wipe them with a tissue or towel. That slows down the build up of tea stains. Once a while, very rarely, i use a mild and un-perfumed detergent and rub the stains off with a sponge, and then use lots of water to wash the detergent off. I don't think that something aggressive like bleach or baking soda is really needed, unless you have an old pot that has decades of accumulated dust and dirt you have to get rid off.
Tea ware with more porous glaze such as hagi i never use anything other than hot water on - stains or no stains.