That's not a Nobel Peace prize medal it's an unissued medal in the Medicine category. Frankly I wonder how and why it got out. They use the same design each year so if they had it left over one year they could use it the next year. It is probably left over after 2010 when they changed manufacturers. As an unissued medal though it's really only worth the bullion value, about $7,400.
I believe it is "plated" in 23K gold (not a solid gold medal), so, really not worth much since it has no recipient provenance. JMO
If you're actually interested in owning a real Nobel medal, they do come up for sale occasionally. I'd only buy from a reputable auction house. The more famous the name, the more expensive the medal. See here: https://coins.ha.com/c/search-resul...ce|1&N=790+231+51&Ntt=nobel&ic4=SortBy-071515 In case your curious, NGC will certify them as well.