This is one of a group of vintage public domain letters that came from a book. It includes diamonds, swirls and curls with a capital letter I contained within a rectangular frame.
This fancy letter I could easily be used alone or with one or more of the other letter images created by the same artist. The other letters include:
Ernets Ingersoll’s publishers decorated his 1887 work The Crest of the Continent with these fancy letter, drop cap images.
This image is copyright free and in the public domain anywhere that extends copyrights 70 years after death or at least 120 years after publication when the original illustrator is unknown.