Photo by my lovely and talented spouse. Don't tell her what to do.
Those familiar with comics will recognize this as the "noncompliant" logo from DeConnick and De Landro's Bitch Planet, carved into a piece of slate. This run used very shallow layers (cutting 0.003 in. at a time) to a mere 0.05 in. deep. You don't need a lot of depth to get some decent contrast. I'm considering getting a dropper of india ink or something to color in the letters. Still, you can tell if you look closely at the textures (or at least I can tell) how ongoing wear is affecting the bit through the run. I'm looking at carving some square-foot slate floor tile into 4 inch squares for use as coasters. Slate, by the way, it quite porous and lets water through easily, so as a coaster, it is, dare I say, noncompliant.
This piece is also notable for temporarily killing my router. The stone carving I've been doing lately has involved running it for hours at a time at high power. The brushes in the router (actually blocks of carbon used to run current through the spinning parts in places where a wire would snap instantly) have finally worn down to the point where they can't keep contact. Fortunately, they're cheap to replace, so I should be up and running again soon.