My treasure of the day...

I'd say 1920s but that's just from browsing on the internet. 

It would be cool if you can trace back who they are.  I mean, your grandmother should be able to at least guestimate who they are.  I mean, she can eliminate the people she knows for sure they are not.  So, she can probably say it's not her parents, her uncle, her this or that.  But she might be able to say something like, "I know my Uncle bob once had a distant brother and wife who I didn't know.  Maybe it's them."   Maybe make a family tree or something.

Because once your grandparents pass, it's really going to be close to impossible to figure it out. 

Very cool!  My ma has all the wedding pictures from our entire family all the way back to my maternal AND paternal great-grandparents.  She may even have some great-great-grandparents' puctures too.  Best part is to see how resemblences carry on.

Good luck!!

My mom saw the picture and called my grandmother. They've narrowed it down to two probable people.  My great-great-grandparents or my great-great-great-grandparents. Either way, a treasure indeed.

 The worse part....my mother says she wants it back! I told her "finders keepers" and she got very upset. I finally conceded, that she could have it, but only if I get it when she dies!

you notice how nobody ever smiles in these pictures?  Looking back at old albums and pics in my nana's house, all the older families never smiled.   Man, was it really depressing back then? 

even some of the women look mad. 

ah, hope you figure out who it is!  

My mom has a bunch of family pictures going back to before the turn of the century and very few people in the ones before WWII are smiling. I asked my great-great grandmother when I was a kid about that and she said that getting your picture taken then was a big deal.

The women on my mothers side are very long lived. If they die before 80, it's "young". 100 is good, but not unheard of.