I have some old oak that came out of some barns I demolished. I believe it is red and black oak. I may use it myself, or I may sell it, depending on it's value. Can anybody direct me to where I can find out how to grade it, and what it would be worth?

I have 2x6's, and 1x material. Some of it is straight, some of it has a bow to it. It's all de-nailed.

Thanks in advance for any info you may have on this.