Here is the block before assembly (just so you know I'm not trying to pull a fast one, lol).
You will find the block in the 1st column, 4th row position in the layout.
Two people guessed this block, Nancy and Mami, congrates, to you! "Well Spotted" as they say on Safari! And thanks to all who made a guess and left comments!
My aim in using these fabrics was to make the block as innocuous as possible and use fabrics that I had on hand. The tan stripe was a pretty good match to one of the fabrics in 3 of the blocks. The shirting fabric (which came from an old shirt) seamed a better match than any of the vintage shirting fabs in my stash. It did seam a bit bright but there are lots of other bright fabs in the original so I did not think that would make it stand out more than some others. I might Tea dye it to tone it down and further camouflage it?
Now the trick will be finding some appropriate border fabric?! I want it to be big enough to use as a bed topper. At present it would only be about 45" square.
Thanks for playing "Find the Imposter"!