This pretty little iris is found in moist fields and prairies. It’s not uncommon in the right habitat. The problem is finding the right habitat.
There are 86 species of Sisyrinchium listed in the USDA Plants database. Obviously the plant taxonomists really enjoyed working with this plant.
Of the 86 species, only 4 are found in Indiana and only 2 in northeast Indiana. The other species is White Blue-eyed Grass which, lo and behold, has white flowers.