Irises: White iris with no name?, 1 by Joan

Joan wrote:
This iris is unnamed in my gardens. I'm pretty sure I got it in the last 3 years since I relandscaped my yard. Might be from a coop? I don't know, but it lost it's marker and I can't figure it out. Any clues to steer me in the right direction?

I have a yellow unnamed too, in another post.

Any help would be appreciated. I really want to change the metal marker that now says "unknown white".

TIA,

Joan