Need help to identify a portrait painting in the frame

Hello everyone. I am new to the world of antique and to this forum. I found this beautiful portrait painting and its frame. Firstly, I am not sure it is a paint or not as it is inside the glass and I do not want to destroy the frame by open it. Lastly, as it has no signature or date, I cannot identify when this was painted. There are several damages behind the frame and some dust (I have tried to clean it). Please, if you have any idea about this painting or when it was painted, I would be very appreciate. Thank you

 

Since it is under glass I would assume that if it is a painting, it would be a watercolor. I tried to expand the picture but it was getting blurry. Could you post a pic as a full size image. I did see some elements that would lead me to believe that it is a print.

 

It seems to be inspired by Cornelis Schut's portrait of Rubens, which in turn was based on a famous Rubens self portrait. The nose is different though.

Cornelis Schut, Portrait of Pieter Paul Rubens:



Rubens' self portrait:

 

As above. A vintage reproduction of an old master painting in a gilded wood frame. These were popular as late as the 1960s/1970s but yours could be a tad earlier. You're right not to have opened back; doing so would have hurt value.

 

Hi thank you for your reply. here I try to put pictures in full size.

 

I can see, it got a lot of influence from this famous piece. Thank you so much

 

Thank you Debora for your thought. Really appreciate it.