Ok, found em, thanks. Now that I have some though, what exactly do you do with them? I processed them at a smelter into "processed ethereal spheres", but I can't find anything that will let me make ethereal bars (which the forges say they need to make weapons out of it.) Is that something you have to unlock?
Thanks for taking the time to answer! 
Melt them. The easiest way to do that is to open your stocks screen, find "ethereal spheres (processed)," hit "m," then queue up "melt a metal object" at a smelter. Because of the way melting works, you'll get the best results if you only queue up this reaction at one smelter. Ethereal spheres melt down to 1/5th of an ether bar, so a batch of 10 from an alchemy experiment will net you two bars. They can't be used for armor, so don't let anything but a moody dwarf or a highly skilled weaponsmith touch them. Ethereal weapons are roughly equivalent to voidshard in strength, but are much lighter - they make fantastic edged weapons.
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If you're curious why all of these steps are necessary, it's purely technical. The spheres are produced as toys to make them easy to find, but toys do not accept the [UNIMPROVABLE] token, which means they have quality modifiers - and, if you have a savant or expert alchemist, this means that masterwork spheres pop up from time to time. Melting a masterwork item causes a severe negative thought (and sometimes a tantrum spiral), but using them up in a custom reaction does not, so the spheres are "processed" into another toy in a reaction that does not have an associated skill, so there is no chance of them being of masterwork quality after that, and they are safe to melt down.
Entities do weird things with custom (raw-defined) reactions that enables them to produce the products during worldgen and from caravans without ever meeting the reaction's requirements. For things like special tools, toys, and weapons, this isn't a problem because an entity will not sell you those unless it is explicitly permitted in their entity file, but for ether bars (because they're bars), there is no permission check. These spheres, therefore, need to be melted at the smelter (instead of used in another custom reaction) because making a custom reaction for them would allow you to request them from the dwarven caravan and would cause caravan guards to start carrying around ethereal weapons, which kind of breaks things. I discovered most of this the hard way.
TL;DR version: It's done this way because this is currently the only way I could get their accessibility right where I wanted it.
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Topic: *=*=* Legends of Forlorn Realms (LFR 2012) v0.21a *=*=* [DF 0.34.11] (Read 403134 times)