Field find - Civil War era??

While detecting a small town nearby I struck up a conversation with someone in the park. He was interested in what I was doing and invited me to hunt a large field nearby that he said his grandfather had disced up Civil War items many years ago. He said there was a small civil war graveyard also on their property near the field. He led me out to the field and I was able to hunt for a short time before I had to leave. There were lots of ferrous targets, no lead or higher conduct items (other then newer cans) found. It has been raining ever since, so haven't been able to get back out. Below is the only item that was interesting.



The quarter is for size. The shaft is tapered, possible to be driven into a hole. There is a collar that would appear to be a stop point on the shaft. The top is hooked with an eye hole. the end of the hook has a bump at the tip on the inside of the curve.

I was hoping someone would be able to identify this whatsit and tell me if it is Civil War period.

Thanks for any help!