Here's the video where I fail to break the thing in two by hand, and therefore resort to a hammer. Spoiler: the printed thing does not survive. Printed by Shapeways in the material they call Full Color Sandstone. The color is printed 1mm deep, and at 3mm thickness it's quite strong enough for normal handling.

"Shapeways' Full Color 'Sandstone' Strength Test" with a Hammer (3D Printing)