I did think there was a possibility that it wasn't a coti, but now that Cambouis got it out of the box we know what it is. It looks like a good stone to me. Give yourself some time to get used to the size. Here's a video honing on a 4x1-1/4 coti that shows a few different strokes that can be used on smaller stones.As David may be suspecting, that stone looks like it could be something other than a coti...
https://m.youtube.com/watch?v=dCtfSAMvuaY