Clean residue on leaded windows

[RrogerD]

Hopefully this shows in the pics.

I have externally leaded double-glazing. There is streaking on every panel that I can only assume to be some form of leaching coming from the lead. We have tried everything to get the staining off but without joy.

Any known and successfully used products we can try?

 

[ronniecabers]

you could try Jewellers Rouge, it will probably help , but depending how long its been like it will depend if you can get it all off