Jostens USMC 1775 - 1945 RING

Please review all photos and ask any questions you may have prior to purchase. Unknown silver tone metal or composition of insert. In the sunlight, it looks purple. Household lighting looks Maroon. I have not attempted to clean the item. It appears to have never been worn and then stored away in the ring hard shell box. I'm leaning towards size 6 based on how this fits my thumb. Includes ring box. 🐓