Possible #359 1909 Bluish Paper?

I have done by due diligence as far as MM size, compared back to others and it looks bluish to the others. 12 Perf. Thoughts from the pro's before I send this in. Thank you.

I think you will find that the advice is to scan your stamp against an orange background.

Your picture is unclear. It, also, has not been taken under correct lighting conditions as is evident from the shadow you are casting on the stamp.

No. For starters, your stamp is perf 11, not perf 12.

First of all, get a perforation gauge. Your "12 Perf" line might suggest you counted the number of tips along the right edge of the stamp. That is not how it works. Perf 12 means there are 12 tips per 20mm of however big a stamp is.
The design height of your stamp is roughly 22mm. So it turns out there are 12 tips over 22mm in height. Subtract 10% and you'd get Perf 11 without using a perf gauge.

For a rough idea about "blue paper", place all/a lot of your stamps face down onto an orange paper. Most likely all your stamp backs will look the same (bluish paper is not _that_ common). If any one stamp stands out in color, then you might have a candidate (or a stamp soaked in contaminated water from colored paper the stamp was glued onto).