I don’t remember seeing this stuff before so I thought I’d share this inexpensive hardboard I found at Home Depot. I think it’s really beautiful stuff made with Eucalyptus fibers. It’s dark enough that there’s not a lot of contrast when engraving, but it has a very nice acrylic finish on top and has a beautiful hand to it. (The color is similar to walnut.) The backside is unfinished and fibrous.
I’ve read through the specs and it appears safe to burn and it’s an environmentally friendly wood. The cured acrylic finish lists formaldehyde, but I’m personally comfortable with it. (That doesn’t necessarily mean it’s safe or that you should rely on me for safety info.)
Here’s a look at it. The dark one has a thick clearcoat finish, the other a thin matte finish.