I have a vague memory of Dr Steve Pieczenik speaking about the watermarks shortly after the election. His statement was that the watermarks on the legitimate ballots were made using a radioactive ink, and were thereby easily identified. It sounded strange at the time, which is the reason it stuck in my mind. But after looking up the definition of fluorescence just now, his statement makes more sense:
fluo·res·cence: the visible or invisible radiation emitted by certain substances as a result of incident radiation of a shorter wavelength such as X-rays or ultraviolet light.
I have a vague memory of Dr Steve Pieczenik speaking about the watermarks shortly after the election. His statement was that the watermarks on the legitimate ballots were made using a radioactive ink, and were thereby easily identified. It sounded strange at the time, which is the reason it stuck in my mind. But after looking up the definition of fluorescence just now, his statement makes more sense:
fluo·res·cence: the visible or invisible radiation emitted by certain substances as a result of incident radiation of a shorter wavelength such as X-rays or ultraviolet light.
I think you nailed it.