A sheet of cheap-on-closeout glass tiles emerged from the back of the Basement Laboratory workbench:
They’re intended for bathroom / kitchen backsplash panels and suchlike, rather than floors. Surprisingly, the white frit backing is diffuse, translucent, and lights up nicely with a backlight, although I lack sufficient hands for a convincing picture.
One can, with some effort, peel the tiles from their foot-square backing mesh, which leaves them covered with the resolutely sticky adhesive:
Applying the razor scraper removes most of the gum, xylene removes most of the remainder, and what’s left isn’t visible through the frit.
They’re 25 mm square and 4 mm thick, with sufficient edge imperfections to require half a millimeter of clearance on all sides
Sixteen pixels would make an adequate display:
Now, if only I could find the matching Round Tuit™ on the bench.