Hohner corona?

I was given this instrument as a gift. I am trying to find out as much as I can about it. I know that is a hohner and I can make out part of the word "Corona". It has 47 holes on the bottom and the bass keys are blocked. All of the keys work. It sounds very strong and clear. It is stamped GCF on the wooden keyboard. Does anyone know about what year or model this is?