Hello and welcome to the forum! Your stamp is from Italy, from, 1863. There's two different types of this stamp: Type I, described as ''First C nearly closed'' and Type II described as ''C'' open. Line broken below ''Q''.
As I can see, there's no broken line below Q, and the first C is nearly closed, can you spot that?
As I saw in my old catalogue, the Type I example (yours) is way more expensive unused (yours), but this is not a reference, because my catalogue is more than 30 years old and the prices may have changed. Also, beware of the fake examples, so that would be nice someone confirms it's genuine or a forgery.
If genuine, I think it would be a really interesting stamp and so a nice philatelic example. As Parcelpostguy. said, it's printed on both sides, I guess it can be considered as an error, or an EFO (error, freak, or oddity).
Hope this helps a little.
