Having established that scribbling Sharpies on laser-cut acrylic is a Bad Idea™ due to stress cracking, I made some acrylic mirror coasters with rattlecan spraypaint on the back:
The colors, which look much more obvious in person, are gray, black, and blue. There should be a diamond to round out the playing card theme, but only three fit neatly on the remaining slab of mirror.
A slide show giving a closer look:
In person, all of the gritty edges and imperfections vanish, because they’re all well below eyeballometric resolution: you can see them, but only if you look hard.
Those are at 500 mm/s and 15% PWM, which is too fast for fine details due to the HV power supply’s bandwidth limitations. However, the tube doesn’t fire reliably below about 10% and tends to sprinkle speckles over the surface, so there’s not much leeway to slow down.
All in all, the outcome is Good Enough™.
The Smell of Molten Projects in the Morning 