Ive started cleaning the misses' grandpa's house, did the first clean last month. Frames were green and windows were dirty as hell, after i bladed white marks appeared around the edges of the lead when the water started to dry. I polished the **** out of them, everything looked sweet before i left. So i assumed it must of come from my washer or wet cloth with all the dirty green from frames. I come back this week and notice a few a white marks had reappeared. So i started on the upstairs front bay, and same thing, white marks appearing again. Its taking alot of time to polish these off as i have to do them a diamond at a time. At this point i assume its coming from the lead? I havent come across this before with other lead windows ive done, so just wandering if someone can shed some light.