Found this R IBBOTSON saw recently, with an "R Ibbotson, Sheffield" medallion I haven't seen before, and an "R Ibbotson, Sheffield, cast steel" blade stamp. The saw has a good handle, although several split nuts have been replaced with rivets. Blade is fairly straight, not badly pitted, 25-1/2" long (after I ground off the jagged toe) There were a confusing and varied lot of Ibbotsons involved in the Sheffield saw business and initially I thought it might be a Richard Ibbotson saw (the only R Ibbotson listed in HSMOBs main listing) Then I found the Robert Ibbotson medallion in Summerfi's saw medallion reference guide (thanks Bob), which has the same shield pattern in part of its medallion, and I did a bit more e-research on Robert Ibbotson. Robert Ibbotson, was co-founder of Ibbotson Peace & Co in 1845, lived in New York for a while and marketed merchandise for Ibbotson Peace (and this is a North American saw), left Ibbotson Peace in 1853 for another partnership, retired 1863. But my saw doesn't look quite that old. However, Ibbotson Peace became WK & C Peace, and continued using the "R Ibbotson" trade name (according to HSMOB and "Trademarks on Base-Metal Tableware"), so my saw looks like it could be a WK&C Peace saw from the later part of the 1800s