AHC: Discover Radioactivity by 1800

Radioactivity OTL was discovered by Madame Curie and by Becquerel in the early 20th century. Given that it is a famous example of a serendipitous discovery in Becquerel's case, could a similar discovery have happened years before? The Joachimsthal mines in what was Austria have been producing uraninite along with their eponymous currency-grade silver since the 16th century, so the original source of the discovery had been present long before the actual discovery. What would it take to have an eighteenth-century or earlier scientist formulate a comprehensive theory of radioactivity?
 
How would he notice it? The easiest route I know is through light-sensitive chemicals reacting. That would require them to be better known earlier. Does the Joachimstal mine produce anything radioactive enough to produce notable heat or glow in the dark?
 
As it turns out, the pitchblende ore mined at Joachimsthal was used as a coloring agent in local glassware. It's phosphorescent under UV light, which is not very helpful for the eighteenth century. The best method I can think of for theorizing radioactivity would be for someone to try fertilizing crops with pitchblende and notice strange results from the experiment.

This guy might be of interest, as he discovered uranium while researching at Joachimsthal. Perhaps a deeper obsession with the stuff could lead him to find out its secrets?
 
As it turns out, the pitchblende ore mined at Joachimsthal was used as a coloring agent in local glassware. It's phosphorescent under UV light, which is not very helpful for the eighteenth century. The best method I can think of for theorizing radioactivity would be for someone to try fertilizing crops with pitchblende and notice strange results from the experiment.

This guy might be of interest, as he discovered uranium while researching at Joachimsthal. Perhaps a deeper obsession with the stuff could lead him to find out its secrets?

Comic books aren't real, it is unlikely anything would happen. What is needed is certain photosensitive chemicals being in close proximity to a pitchblende long enough for someone to notice that they've been exposed to something that isn't light.
 
You need an earlier development of photography which would require an earlier development of modern chemistry by at least some 60 odd years.
 
As it turns out, the pitchblende ore mined at Joachimsthal was used as a coloring agent in local glassware. It's phosphorescent under UV light, which is not very helpful for the eighteenth century. The best method I can think of for theorizing radioactivity would be for someone to try fertilizing crops with pitchblende and notice strange results from the experiment.

This guy might be of interest, as he discovered uranium while researching at Joachimsthal. Perhaps a deeper obsession with the stuff could lead him to find out its secrets?
Martin H. Klaproth (This guy) was according to wikipedia the leading chemist of Germany in his lifetime (1 December 1743 – 1 January 1817) Klaproth seems to have had a very international outlook. He was elected a Fellow of the Royal Society in 1795 and a foreign member of the Royal Swedish Academy of Sciences in 1804. He also appreciated the value of quantitative methods and was one of the first followers of the Lavoisierian doctrines outside of France.

Now the interesting thing is that at the same time Thomas Wedgwood (14 May 1771 – 10 July 1805) was active. Wedgwood is credited with a major contribution to photography and technology, for being the first man to think of and develop a method to copy visible images chemically to permanent media.

In his many experiments with heat and light – and possibly with advice on silver nitrate from his tutor Alexander Chisholm and from members of the Lunar Society – Wedgwood first used ceramic pots coated with silver nitrate as well as treated paper and white leather as media of print, and had the most success with the white leather. Although he originally tried to create images with a “camera obscura,” his attempts were unsuccessful. His major achievements were the printing of an object’s profile through direct contact with the treated paper, thus creating an image’s shape on paper, and, by a similar method, copying transparent paintings-on-glass through direct contact and exposure to sunlight. The dates of his first experiments in photography are unknown, but he is known to have advised James Watt (1736–1819) on the process of photography, circa 1790 or 1791. Watt wrote to Wedgwood...

"Dear Sir, I thank you for your instructions as to the Silver Pictures, about which, when at home, I will make some experiments."

So it wouldn't be to far fetched to get Klaproth interested in early photography. So you get the discovery of radioactivity around 10 to 1 year earlier than your cutoff date 1800.
 
I figured I'd necro this rather than create a new thread.

Let us assume that Herr Klaproth meets Mr. Wedgwood and becomes interested in photography. The chemist attempts to document the extraction or uranium from pitchblende in photographs, or rather silver nitrate on leather being exposed to sunlight minus the silhouette of the photographed objects. He finds that the raw ore exposes the nitrate, as does the extracted uranium. He later exposes both without sunlight, and finds that a sort of "invisible glow" emanates from the rocks. As the leading chemist of Germany, he publishes, making famous both the *radioactive nature of uranium and the photographic process used to document it.
Now all of Europe is familiar with Herr Klaproth's magic powder, and leading scientists go about trying to explain this newly found *radioactivity. As a result, we might get the earlier production of uranium metal, potentially usable for artillery shells and potentially making Canada very, very rich. Charlatans left and right start selling the powder, claiming that its invisible glow is the "essence of life," and I imagine some royalty would buy into it. But without the development of a theory of radioactive decay and thus the discovery of isotopes, the only radioactive substance known to man will remain U-238. Despite marginally better artillery as a result of greater interest in uranium and a few gimmicks with yellow cake and silver nitrate, I can't think of any uses of U-238 in the early 19th century.
The other side of this discovery would be a greater interest in photography to find other *radioactive substances. Aside from perhaps monazite ore and the resulting discovery of *thorium, it's not really possible that any other elements would be discovered. However, the new importance of silver nitrate would certainly speed the development of photographic plates for detection of *radioactivity and, for consumers, amateur photography. Perhaps photography gains a ten- or twenty-year advance over OTL.

Dies this sounds somewhat plausible? What would the ramifications of such a discovery be?
 
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