I haven't a clue, but I'll look under the sink when I go to rinse out my teacup.
My brother, a joiner who insists that the blades of older, Victorian & Edwardian tools are far superior to modern ones, (and I have seen one of my Dad's planes do the under it's own steam downwards paper thin shaving) watched me polishing up a knife with the paste and disappeared out to the workshop with it. He was impressed enough to go and buy some for his own workshop.
Excellently informative thread; thank you all.
cheers,
Toddy
