When I was doing the same we found two bibles from the mid 1850's, they must have been handed down. We donated them to 2 local churches, they were valued at around £500 each but my Mum and Dad wouldn't have wanted us to make money from them.Thanks mate, I had no idea. She never mentioned it. Only going through her stuff revealed it.
It's very distressing dispersing your parents belongings, shedding tears is almost impossible not to do.