Looks like stove wood -- rather short lengths. I don't blame you even if it's not stove wood. Those pieces are so dense they would barely float. Picking them up will be a challenge and perfect training for U.S. Olympic athletes who might volunteer to help load your truck with them.
I used to love working with hickory to make furniture. Three of the end tables in my rec room are hickory. They remind me of that whenever I try to move them around.
Slacker, your saw got one whale of a workout, and so did you. Two thumbs up!