After some research I found that this was the seal of Kappa Omega Alpha. KOA was a fraternal "secret" society on the campus of Phillips Academy in Andover, Massachusetts. Founded in 1874, the group was disbanded in the late 1940s.
http://heritage.noblenet.org/items/browse?search=k.+o.+a.&submit_search=Search
That site has some pictures of the symbol from my plaque.
I was only ever able to find one other one like it online and he also could not find much info about it. I am curious to know if it has any value. Thank you.
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