Judging by what I think is a 4 inch wide piece of oak on an end table top your item could be a 7 inch long by 1 inch wide metal strap of some kind with a hole in one end. I have no clue to the type of metal, but my best guess it's made of aluminum based on the blacken color and chipped edges and looks to have been washed up on the sands of a shoreline by the waves over and over. I wouldn't think it would be much older then maybe 20 years. It could be anything that was used on anything.
You've no clue of the type of metal its is? I still think it looks like aluminum, maybe, just maybe pewter?? Go find a magnet and see how it reacts to this mystery item. We may have a long ways to go, being it has those weird lines on it. My pen is 5-1/2 inches long. I'm like only 2-1/2 inches off the first try. Not to shabby if I say so myself. ;-)
I agree pulltab, but the problem is there's a hole in the end?? It must be a knife of some sort... But the lines on it make it seem like something else??
Omg I think you solved the mystery! Thank you so much Charlie! I'm gong to look up some other plotting dividers and see if they have similar lines on it... You the man