Before saying anything- I have researched this.
- Almost all search results are from 2009 or worse, like this:
Given that uranium is one of the most common heavy elements in the crust, I think that the dwarves should be able to collect and refine it. Since normal uranium is quite stable it wouldn't give much damage until after prolonged exposure, which is why heavy utility dresses made from cloth and metal (preferably lead) would be made by tailors. GIven the density and melting point of uranium it would require a magma furnace to melt into bars. <P>In the next step, given dwarves' skill at mechanical constructing, they should be able to make enrichment centrifuges to turn the low-grade uranium into plutonium. The centrifuge itself could be driven by pack animals and would require a number of high-grade mechanisms as well as much metal. This off course would also require a skilled alchemist with an adjoining laboratory. Since enriching uranium yields more intensely active isotopes handling them would require master-woven utility suits. <P>Enriched isotopes could then either be used in a reactor to produce enormous steam, heat and/or pressure, perhaps to create a steam catapult for sub-orbital bombardment of other kingdoms, fortresses or hostile strongholds, or as delivery systems for orbital deliveries, which would tie in with DF's space arc. The material be packed into metal containers with conventional explosives (produced by alchemists) for being terminally introduced under intense pressure to achieve critical mass enough to set of a thermo-nuclear reaction. The production of this encasing would require skilled weaponsmiths, alchemists and mechanics. <P>Dwarves are hardy, of excellent constitution. Even so, children born, especially those in close proximity to enrichment centrifuges, reactors or weapon storages, and perhaps even to a lesser extent, those close to uranium stockpiles, should increasingly exhibit mutations. To make this simulationally more interesting, rather than create a high proportion of severely handicapped or inviable offspring, we could reduce the nativity but make the survivors have interesting effects: extra arms and eyes (which on the one hand make them good fighters due to multiple redundancies, but on the other hand requires specialised armour), or even mental deficiencies (tree-fancying).<P>The risk of nuclear strikes also makes deeper fortresses preferable in that they alleviate mortal anxiety and reduce unhappy thoughts.<P>Finally, weapon stockpiles have a new function in that they now can affect diplomacy and negotiations.<p>
- And they are all roughly the same: mine it, enrich it, wacky hijinx, don't forget mutations and cancer.
Since steam and steampowered machines are out, what about including uranium ore, refining or enriching it and use the result in either crude reactors or as simple heat sources. The heat sources could be exported as a way of melting ice in cold climates or substituting for magma in places far from volcanoes.
Of course, it would give the dwarfs(and anyone else nearby) cancer (or maybe even mutations) and serve as a way of limiting the lives of characters.
So, what does Toady have to say about this?
[before the raws for pitchblende] this is uranium oxide, but was possibly used for glazing ceramics (colored glass most likely came later involving refinement beyond our tech level)
What does Wikipedia have to say about this?
Triuranium octoxide occurs naturally as the olive-green-colored mineral pitchblende. U3O8 is readily produced from UF6 and has potential long-term stability in a geologic environment. In the presence of oxygen (O2), uranium dioxide (UO2) is oxidized to U3O8, whereas uranium trioxide (UO3) loses oxygen at temperatures above 500 °C and is reduced to U3O8. The compound can be produced by any one of three primary chemical conversion processes, involving either uranium tetrafluoride (UF4) or uranyl fluoride (UO2F2) as intermediates.
So, to actually
refine pure elemental uranium, dwarves need pure fluorine. This is impossible no matter how much ‼dwarven science‼ you apply. Even better, enriching it involves either more fluorine or dwarven centrifuges. Uranium ingots are right out, slightly enriched fuel rod uranium even more so, and enriched atomic bombs are so right out that they're almost left out. Don't even mention plutonium. But what else does Toady have to say?
Wikipedia has a source claiming the year 79 as the earliest confirmed date, and another for the late middle ages, which is what I was going by, although it says its use was popularized later on.wikipedia on uranium glass
Huh! This contradicts the raws. Of course, it's a complicated, controversial issue and tech levels are hard to deal with, but using pitchblende only to glaze dwarven ceramics is a crying shame, so let's assume that a) dwarves are clever bastards and b) glazers usually get enlisted in the zerg rush wrestling squad because nobody likes glazing. So what are our current uses for pitchblende?
1. Glaze ceramics: Toady-approved, hopefully not controversial, Fiestaware.
2. Make uranium glass: More controversial, could be possible, leads to neat light green glass.
For uranium glass, let's say it's more valuable than even crystal glass, or equally valuable: pitchblende and rock crystal are both rare in-game. To be fair and just, we could also add lead glass, although I don't know how valuable that should be. How will we craft this madness?
1. Glaze ceramics: Reaction at the kiln: pitchblende boulder → pitchblende glaze. Glaze as normal.
2. Make uranium glass: Glass furnace: Take raw clear glass and pitchblende boulder → uranium glass. This should work.
Now let's open a horrible issue: radioactivity. Mutations are a stretch, and cancer isn't implemented yet, so maybe working with pitchblende can release little bits pitchblende dust on occasion, which causes COUGH_BLOOD when a lot of it has been inhaled. This shouldn't be too hard on the raws and it's pretty realistic.
There's one other radioactive metal that occurs in high-ish quantities: thorium.
Thorium has been extracted chiefly from monazite through a complex multi-stage process. The monazite sand is dissolved in hot concentrated sulfuric acid (H2SO4). Thorium is extracted as an insoluble residue into an organic phase containing an amine. Next it is separated or stripped using an ion such as nitrate, chloride, hydroxide, or carbonate, returning the thorium to an aqueous phase. Finally, the thorium is precipitated and collected.
Several methods are available for producing thorium metal: it can be obtained by reducing thorium oxide with calcium, by electrolysis of anhydrous thorium chloride in a fused mixture of sodium and potassium chlorides, by calcium reduction of thorium tetrachloride mixed with anhydrous zinc chloride, and by reduction of thorium tetrachloride with an alkali metal.
That means "too much work". No thorium.
Other ideas could involve radon being released, but honestly, if you want to start with complex poisoning, start with lead, mercury, and arsenic. This suggestion is silly and out of place, but I just wanted to put everything in one spot and make it somewhat recent. Besides, uranium is fun even without bombs.