I have a habit of drinking tea on the job. And not drinking all of it because I let it go cold. Doing a lot of concreting at the moment
Imagine my surprise then when I took the mug out of the dishwasher to find concrete spatters all over the inside at the bottom of the mug - even after a hot wash.
Reusing the mug, the concrete makes no difference.
Better keep this one quiet before the HSE gets in on the act