Possible victorian hinges

[novausc]

I purchased a house that can be confirmed existing in 1888. We believe it to be older. While cleaning the basement I found three old hinges that were covered in rust. After looking more closely at them, I realized it wasn't their rust but rust from other iron objects in the bucket with them. After a light cleaning with vinegar, salt and flour, they appear to be copper. They don't appear to have been plated and a scratch test shows them to not be copper on something else. They are not magnetic. All I can find through research is brass and bronze hinges. There don't appear to be any makers marks. They are quite large and heavy. Can anyone tell me anything about them or point me to a resource?