I often deal with chips that are decades old by now, and I've always wondered what goes into the recipe for the ceramic casing. What are the raw materials, how is it produced, etc.?
Also, how are components in general labled with the letters and numbers? It's very heavy-duty material, as very few cleaning materials will obliterate it.
I realise it's a bit OT, but where do the world's Barium, Americium, Osmium, Tungsten, and all the other wierd rare metals come from? So far there's been no "HEAVY ENGINEERING: Tungsten mines!" on the Discovery channel.
In the specific case of Osmium (sticks in my head, because - ) it's worth about 80 times more than gold, so is it dug up in hi-security? Or is the somewhat limited market security enough?
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if love is a drug, then, ideally, it's a healing, healthful drug... it's kind of like prozac is supposed to work (without the sexual side effects and long-term damage to the brain and psyche)
Heh, good point. :)
Barium comes mostly from barite (barium sulfate) and some witherite (barium carbonate). Barite of course is probably familiar as the "chalky milkshake" that gives the gastrointestinal tract good x-ray visibility. Barium is nicely poisonous but this works because barium sulfate is a highly insoluble salt of a strong mineral acid and nothing much can displace it so it just goes right on through.
For processing, they have to get it into a more useful form to seperate it on a large scale during processing, but I don't have the slightest idea how they'd do that. Possibly they could mine selectively enough to get a like
80% rich ore or something, then reduce the sulfate to sulfide with carbon at a yellow heat. From there, you'd oxidize the sulfide to sulfur (byproduct), leaving barium hydroxide, chloride, or whatever else you choose.The barium carbonate I have (ceramic grade) definetly has sulfide impurities, because when I make barium chloride with it, it stanks.
Tungsten is probably mined like any other heavy metal, seperated from gangue by flotation and/or density (tungsten minerals are dense), acidified (to free tungsten hydroxide, i.e., tungstic acid) then leached with a basic solution, since sodium tungstate is soluble. The same would apply to molybdenum, whose chemistry is similar AFAIK. Then you just reduce it to metal, and, uh, well it's hard to melt into ingots so you'll mostly have to live with powder. ;-)
Americium of course is seperated from fission reactors, where uranium undergoes neutron absorbtion and other nuclear reactions which increase Z (atomic number). After some time in the pile, the fuel is dissolved and the americium (and others) is seperated chemically.
Heh, gnaw- platinum group specimens are probably worth more to museums and private mineral collections than on the market. Such items are exceedingly rare. A lot of the rare elements, for example selenium, tellurium, PGMs, etc. are a result of refinement, usually by a very selective process such as electrorefining (or electrowinning) or the brutal chlorination of something like molten gold (yum, chlorine at 2000°F!). Freshly smelted copper for example oftem holds impurities of Se, Te, As, Ag and so on. If you dissolve this through a solution containing only Cu ions (especially with some chloride ions, which *loves* silver ions and will precipitate it), 99.9%+ purity copper will plate out, leaving the impurities either in solution (not so good) or as a sludge (very good). Further refining on that yields your trace elements.
Cadmium was discovered as a fume inside zinc smelter stacks. It has similar chemistry to zinc so is found in zinc ores, but since it has a lower boiling point, not much would be condensed off the smelter, leaving it to go up in smoke, occasionally sticking to the flue. A few other elements work the same way.
Eh, that was a much longer post than such a diagonal comment deserved...oh well...
If you want to learn more, a good historical reference is De Re Metallica. Doesn't cover the less common and/or hard to win elements, but hey, it was the 16th century. ;-)
Tim
-- Deep Fryer: a very philosophical monk. Website:
Actually I've found me a couple of really good periodic table sites, tho you've added things they didn't say. Thanks a lot for that utterly useless knowledge, the kind I treasure most!
Build real live periodic tables, with the noble gases in electrified tubes so they glow, and actual samples of most elements. For beryllium they have the metal, and a hi-voltage ceramic beryllium oxide insulator used in industry. Etc. Extremely interesting. Lithium has the metal under oil, and a few lithium carbonate anti-loony pills.
Anyway sorry to answer my own question, but you might find it an interesting site. Prices start from $40,000!
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if love is a drug, then, ideally, it's a healing, healthful drug... it's kind of like prozac is supposed to work (without the sexual side effects and long-term damage to the brain and psyche)
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