I've been compiling a grit comparison chart for various sheets,
stones, &tc. I've got responses from several sources including
Monsanto, E-Z Lap, and several other sources. I just went to Norton's
webiste and sent them an e-mail requesting technical specs on their
In the product search page, under "Application", there is a selection
for "Sharpening plane blades and chisels" among a list of others.
"Zz Yzx" rhymes with "physics"; or " Isaacs" if you prefer.