A spinthariscope (/spɪnˈθærɪskoʊp/)[2][3] is a device for observing individual nuclear disintegrations caused by the interaction of ionizing radiation with a phosphor (see radioluminescence) or scintillator.
[4][5] While observing the apparently uniform fluorescence on a zinc sulfide screen created by the radioactive emissions (mostly alpha radiation) of a sample of radium bromide, he spilled some of the sample, and, owing to its extreme rarity and cost, he was eager to find and recover it.
[8] Spinthariscopes were quickly replaced with more accurate and quantitative devices for measuring radiation in scientific experiments, but enjoyed a modest revival in the mid 20th century as children's educational toys.
[9] In 1947, Kix cereal offered a Lone Ranger atomic bomb ring that contained a small one, in exchange for a box top and US$0.15 (equivalent to $2.05 in 2023).
[citation needed] The American History Museum of the Smithsonian has several spinthariscopes in its collections, and an article discussing them.