I decided to use this task as an opportunity to do something I should be doing anyway.

So I grabbed my trusty magnet wand...



...and headed to the floor under my sewing table.



In progress...



And these were the results!



The pins on my magnet wand were detected with the wand, the ones to the right were detected with my eyes. (Which is still better than with my feet, which is what I was trying to avoid.) Even though they look identical to some of the ones that the wand picked up they won't stick to it. Go figure.