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The graph you linked shows that this is not true. See the tiny purple graph at the right side of the bar? That's the rare earth minerals and their amount in an

• moloch-hai 4y ago
  Right, says "0.5 kg 'rare-earths'" per vehicle. A biggish camera drone uses more.
  • aeyes 4y ago
    What is so special about a drone?
    • moloch-hai 4y ago
      Weight matters. They are all electric. They have electric motors made with permanent magnets.
• culi 4y ago
  Isn't 0.5kg per vehicle a lot for rare earth minerals?? Sure it looks tiny compared to the amount of copper, nickel, manganese, etc used, but the whole point is that they're rare... 0.5kg of neodymium is around $200 and it's probably the cheapest of the rare earths 0.5kg of europium is around $3,750 Obviously lots of variation there, but maybe ratio of how much it costs vs the total cost of all the other minerals is a better metric to use here than pure weight
  • kragen 4y ago
    ferrocerium is the cheapest of the rare earths, but if we're talking about purified elements, cerium and yttrium are probably cheaper than neodymium the reason the purified elements are expensive is that they're so hard to separate from each other rare earth elements aren't actually rare they're called that because we've inherited alchemical terminology from the 18th century when alchemists were first starting to discover that there were more than four elements, and that in particular there were several different kinds of earth, such as magnesia, silex, etc., and as it turns out things like thoria are in fact quite a bit rarer than silex
    • culi 4y ago
      > Because of their geochemical properties, rare-earth elements are typically dispersed and not often found concentrated in rare-earth minerals. Consequently, economically exploitable ore deposits are sparse (i.e. "rare"). For the purposes of this conversation, which is about economics not geochemistry, they are in fact rare. At least the minerals are
      • moloch-hai 4y ago
        But they are, in fact, not.
      • kragen 4y ago
        ore deposits that aren't economically exploitable are uneconomic because the price in the market is too low to pay the necessary costs, which are higher when the concentration is lower all this means is that there is a wide range of concentrations among ore deposits it doesn't have anything to do with how high those prices are or how rare the minerals are, and as you pointed out upthread in https://news.ycombinator.com/item?id=34357834 https://news.ycombinator.com/item?id=34357834, the prices are pretty low you said neodymium was US$400/kg; gold, the standard rare element, is US$60893/kg today
  • moloch-hai 4y ago
    > "point is that they're rare..." They are not, in fact, rare, as is almost always pointed out when they are mentioned.
    • culi 4y ago
      > Because of their geochemical properties, rare-earth elements are typically dispersed and not often found concentrated in rare-earth minerals. Consequently, economically exploitable ore deposits are sparse (i.e. "rare"). Regardless, they never show up in a pure form in nature so what we should really be looking at is how common minerals that they're easy to extract from are not how common the atom itself is. And the useful rare-earth minerals are indeed "rare"
      • moloch-hai 4y ago
        Vanishingly few things show up in "pure form", anywhere in nature. Gold is is all mixed up into quartz, save for flakes in riverbeds. Nitrogen and argon, famously unreactive, nonetheless come mixed with the other, with oxygen mixed in besides. Diamond, almost pure carbon, is the only that comes to mind. So, it is meaningless to single out lanthanides for this. What does distinguish them, instead, is that they are expensive to separate from one another. In certain places such as Yterby and the site mentioned in the original article, ore contains a concentrated mix of many lanthanide compounds. It remains a chore to get the praseodymium and the neodymium into separate ingots.
• sophacles 4y ago
  That's not a particulary strong argument... The amount of magnesium in the human body is .1% by weight. That's not too far different from the amount of rare-earths in an EV. In the case of a human, i would not wish magnesium deficiency on them, it is not fun, can have severe long-term consequences (such as death), and generally is something that medical professionals will find concerning. In the case of an EV I don't know what the consequences of removing rare-earths would be, but the fact that it's a tiny percentage of total mass doesn't imply that they can just be dismissed.
  • moloch-hai 4y ago
    It means you don't need very much of it. And, now that iron-nitrogen magnets can be used in place of the lanthanide magnets, much less will be needed.