black walnut help please [View all]

We have a couple walnut trees that came with our house. I assumed they were black walnuts. They were too young to have nuts when we moved in, and this is my first year trying to harvest them.

I tried storing a few (a dozen or so) inside in a basket to ripen a bit because they felt pretty hard. Those promptly turned black and molded. So I thought I'd try gathering fresh ones and smashing them open. That went okay, but I got to see the inside of a couple that I smashed too hard, and inside the hard shell, the nut is squishy soft even though it doesn't seem to have signs of rot. Also, the shell inside the husk is surprisingly white - like eggshell white. So are they not black walnuts?

Am I doing this wrong? Should I keep smashing husks off, and store the nuts-in-the-shell for a month or so to harden?