I was looking through a kiloware of older canadians I purchased recently when I stumbled upon this one which I thought was a color I've never seen for #37 / #41...
I have to admit, I'm having a hard time sorting out #37 from #41 by color alone as there seemed to be infinite shades.
But that one definitely struck me as something unusual. Looked through my collection and found one that was close enough and that I had previously identified as a 37, then looked at the paper (looks like a wove), then got the gauge out and, whoa, 12 1/2 x 12 1/2 ????

Never had that gauge on a 37 / 41. Unitrade says it's a 37d, but it's too good to be true right?
Looks like I need this board advice!
First is a scan of the stamp to the right of what I think is a 41a rose carmine

Then, photos with the gauge. The color difference is due to yellowish lighting.
First 12 1/2 vertical :

12 vertical :

12 1/2 horizontal :

12 horizontal :

To be honest, the horizontal gauge is probably more like 12 1/4, but the perfs on both horizontals are a bit worn out.
Anyway, somebody got an idea or comments to share about this one?? :)