Several bar flies have asked for info on refining Tungsten ore. Here goes. A bit of metal history first (Virginia, back me up on this) the discovery date for most metals that you see in the books only tells you when some PhD published a peer reviewed paper about his findings. In many cases, people in the field knew of it long before. As an example, Welsh miners cursed Cupro nicko (Nickel) long before it’s official discovery. Ancient Tin miners also cursed wolf metal, Wolfram, because it ate their Tin. We should not need to mine the W, just work old tails piles. Much easier that way
Tungsten ore is found in three forms: WS2 (rare), CaWO4 (Sweden) and (FeMn)WO4. We need the Mn just as much as the W, so don’t waste it. The first process is gleaned from the 1958 “Rare Metals Handbook”. First, the ore must be reduced to face powder size. We today would crush and grind, but that monster equipment and the alloys to build it, just will not be available for a long time. See my Chromium Report in Slush. We will need to use the sand blast method, I like wet to stop all the dust. The good ore will only be about 2% W, so we must use tables or jigs for mineral dressing to get it to at least 60% W. Easy. Then we boil it in a 50% solution of NaOH in a Wrought Iron pot. Stand back. Cool and decant the NaOH. Wash the ore and add it to HCl dilute solution in a ceramic pot, decant and wash. The W is soluble, the Fe and Mn are filtered out. Arsenic and Phosphorous are removed with Magnesium Chloride. Molybdenum is removed by adding Sodium Sulfide and precipitating the Tungsten with Calcium Chloride. We mow have a very fine powder (1/2-2 micron max.) of Tungstic acid which is dried and fired to oxide, which is reduced to metal with carbon black, which is heated in carbon boats to about 2000F. The Cambridge process (see future tech) should be able to do the same thing, but will take more work. There is a brand new process that uses molten Sodium, but don’t go there! The best of all may be a brand new process that uses bacteria directly on the raw ore, but that one is a LOOOONG way down the road. The metal has a melting point of 6130F, so don’t even think of melting it, we must press it at about 40tons/sq.in.and sinter it to get something we can forge and swage and draw into wire or roll into sheet.
If we do it right, it will be ductile, strong and stiff. Screw up just a little bit and make junk Here it is, have fun
Chuck Dtiman