I am trying to figure out what substance in cow's milk would not burn out in a firing. It is only about 70 miles from Kiev to Chernobyl.
Back a bit, we had this thread w/videos. The Tibetan potters sealed their low-fire wares with a mixture of barley powder and yogurt whey.
Wonder if the Ukrainians are using raw, unpasteurized milk? And, would chocolate milk give you a tenmoko?
So, do you think it would work like an old school casein glue to seal the inside? Maybe something else mixed with milk? With the translation of the second link from Stellaria it seems like the milk is fired into the pot. Perhaps it is just a very low carbonization of the "glaze" turning the pots blackish? Prices seem dirt cheap, (pun intended) but then I don't know the cost of living in that part of the world.