Diggummup-The small mark on the back has no markings but i did e-mail the Audiovisual Curator, Photo Archives and this is what they sent back. So i would think it dates this sometime between 1870 to 1878.
Dear Dennis,
Although I'm not sure of the medallion's purpose, I do know that it is of the official University seal. This version of the seal was used from approximately 1878-1914. The University was founded in 1870 and originally called "The Agricultural and Mechanical College of Ohio". The name was changed to "The Ohio State University" in 1878, and therefore the seal was revised.
I have attached a PDF to this e-mail that contains some documents regarding the seal. The first page is from the Board of Trustees minutes of March 8, 1871. It is an explanation of the design of the first seal. The second page contains a photocopy of the first seal (1871-1878) and a copy of the revised seal of 1878. The third and fourth pages gives a little more explanation of the history of the University Seal.
It appears from our files that we have one of these medallions in the Archives' collection. There was a letter from a gentleman who found what sounds like the same medallion in Vandalia, Ohio - near an old canal. Unfortunately, I could not find any details on whether this medallion was originally mounted to some surface, or if it was given as is.
I hope you find this information helpful! Let me know if you have further questions.
Best,
Michelle
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Michelle Drobik
Audiovisual Curator, Photo Archives
The Ohio State University Archives
2700 Kenny Road
Columbus, Ohio 43210
Phone: (614) 292-1767
Fax: (614) 688-4150
Web:
http://library.osu.edu/sites/archives/photos