Silver frame ID help

Hi! I have several silver picture frames best guess they are 1960's? The overall frame
is 12 x 15” with 10 x 12.5” picture size. The only hallmark of any kind that I've been able to find is "831-13" stamped on the lower left on back. I have been unable to find any information for this mark. Is anyone familiar with it?

 

Would likely help if the whole item could be seen. Where did you get it?

 

It is not a hallmark. A hallmark is an official assay mark. Not all countries have those.
The number is probably a model number or another kind of manufacturer's code.

 

I will post a photo of the full frame asap. The frames have been in the family for well over 50 years. They were likely purchased in New York City or Westchester County NY. I have checked all the frames for hallmarks/makers marks, but the only thing in them is the stamped number which is identical on all of them. Now that I think about it is possible they were purchased at B. Altman or another such store.

 

can u test for silver content?

 

A few more photos.

More photos...

 

silver coloured .....?

 

That doesn't appear to be silver.

Debora

 

Agree.

 

Thank you all for your input. It is silver, another was sold at auction. When I dropped it off at the auction house weren’t familiar with it. And I was never able to get follow-up information from them. Since I haven’t a way to check silver content I will take it to someone who can.
Thanks again for all the help!!!