Help with identify this strop please.

My mom gave me this strop which used to belong to her uncle when she was a little girl and all the men of the house used str8's. It is about 18in long, dark brown leather, but looking on the white (linen?) side that touches the leather, it appears reddish. It may say 'Silk Finish' on the back, hard to tell. There also looks to be something on the leather near the hook, but this thing is old and I can't really tell. The pic doesn't show it very well. The hook says made in the USA if that helps. Does this strop appear useable? reconditionable (I made that up)? valuable? junk?
Any help is greatly appreciated.