HMMM, something I could sell! LOL I have never sold anything that I found, but it is good to know, maybe the ranch owner would like to keep them to repair some of their wagons and such. Thanks for the great information!Square nuts, and square bolt heads are older, and I believe they are no longer available. The hex nut and the hex bolt head is all there is now, but there was a long overlap time, so it would be difficult to date using that criteria. In the early 60's I restored a buggy and was able to purchase the proper carriage bolts and square nuts from a hardware store. But by the 70's they were getting really hard to find.