I was in the local Sears the other day and found that they carry several different types of polishing compounds formed into bars that look similar to the bar of green chromium oxide I recently purchased. The Sears ones only said "Heavy Duty", "medium duty", "high gloss", etc., but didn't say which compound was made of what. The coursest was white, then green, then red, I think. Has anyone used these for stropping? Price was a little over $2 a bar. Please help.