0.1mm Cross - Can I call it microns now?

Here is a cross made from 0.1mm squares, or 100 microns on a side. Etched into sharpie on a glass slide with a 0.3mm base conical nichrome tip. This is not my sharpest tip but at least the lines are relatively consistent in width on X and Y unlike the hypodermic needle tip. I'm now running into the limits of Sharpie as a substrate. I think I can call it micron scale now with some plausible justification.

Calibration slide shows 0.05mm or 50 micron squares.