I tried it myself. There are a lot of articles on the web on how to do it. Technically, it isn't difficult. I used a small SS box, loaded it with the lever (an 1899) bone meal fertilizer and small strips of leather, heated the whole thing on the charcoal BBQ, then when the box was red hot on the bottom (hot as it would get), I popped the top off the box and dumped the whole mess into a bucket of water with some oil on top. The finished product showed a reasonable amount of color, but it wasn't a great job and kind of splotchy. I figure if I messed around a bit and tried it a few more times, I would have got it but, I didn't bother repeating the process. Proved the concept out, but that was about it.