Hi Anne,
It's a bit hard to tell what type of photograph it is from the scan you've posted. Do you have the original photo? Is it possible to post a scan of the whole thing (shrunk down), with colours as close to the actual photo as possible?
By the date it's more than likely that it's a silver gelatine print but if I can see the colour then I can probably narrow that down a bit.
Cheers
Prue
P.S. Also have a look at the top of the PHotograph Restoration board, there is a topic called "COnservation of Original Photos" and in there is a list of websites you can use to identify and give a date to your photographs.