It would be sub-10%* gold content. We're talking about gold doping, specifically substitution in the Pb(1) site, not an alloy.
ETA: I was off by an order of magnitude (originally I said sub-1%) because the doping is extensive, and the mass of the lead/gold is a dominant fraction of the total. The formula given in the paper is (subscripts in brackets):
Pb[10−x]Cu[x](PO4)[6]O with 0.9 < x < 1.1.
Similarly for Au we would have Pb[10−x]Au[x](PO4)[6]O. Taking the centerpoint x=1, this becomes Pb[9]Au[1](PO4)[6]O. In other words, there would be one gold atom for every 9 lead atoms.
The "unit cell weight" is 2647.59 g/mol, and the molar mass of gold is 196.97 g/mol, so in fact the hypothetical gold weight content is about 7.44%, not sub-1%.
That said -- presumably superconducting transmission wires would be thinner than the ones we are used to (a function of critical current rather than resistance). So I'm not sure that we'd have a theft problem worse than we already have with copper.
7.44% gold? That's ~$75 per oz of material. And you're talking about lead cable. Its kind of heavy, even if its thin. And it seems really easy to melt and separate. Notably, most power lines are actually aluminum, which is probably where people would really want this. Also chosen for its low weight / density, cause if you're gonna hang lines 100's of feet long, you want 2700 kg/m3, not 9000 kg/m3, and definitely not 11000 kg/m3. Although probably also significant applications in mm, um, and nm scale wiring.
At the end of their comment it notes that because it's a superconductor it would be thinner.
Perhaps assume an aluminum cladding for strength? Depending on how strong of a superconductor it is perhaps it's only 1% superconductor and 99% aluminum on top of the 10% content. So 0.1%?
I dunno, all these metals will be valuable in the future. Just saying, there's another large factor in estimating the gold content (conductivity saturation) that we don't know what it might be.
The superconductor itself would be 7.44% gold, but the wire would probably be much less -- superconducting tape isn't particularly strong so it will probably be wrapped up in layers of insulator and support wires.
I think that's right. There's no indication that it's mechanically strong, so you'd have it wrapped in layers of rubber/epoxy and steel cables in order to suspend it between power poles or transmission pylons.
YBCO tape has a critical current in the 1-10 MA/cm2 range, so if the properties of this RT stuff is anywhere close, the actual superconducting element of the wire could potentially be very thin.
Having to handle lead for a practically unretrievable amount of gold would (I hope) be enough of a deterrent for the vast majority of "citizen scrappers". Worst case, I think a Pb/Au scrap grey-market would look something like the current catalytic converter market, where raw materials are purchased at set rate by an intermediary and then sold for further processing. Most people know there's gold in their computer parts, but still opt for the recycling bin/ziploc bag in a junk drawer.
There's a wide space between "can be recycled" and "profitable enough that there's theft for base components that can be resold". That doesn't mean it won't be profitable to harvest the gold (I don't know), but one does not imply the other.
For example, paper recycling is profitable when centralized (barely), but even that's with most the pipeline subsidized, and it's not profitable to the degree that people are stealing paper to turn in because it's worth the effort.
paper recycling is profitable without any subsidies at all, and people do sometimes steal paper to recycle it
here in argentina there are tens of thousands of people who make a living by recycling, sorting through whatever trash they can get access to in order to find materials with enough resale value to scrape by. they haul plastic sacks or two-wheeled carts all over the metropolitan area, stacking them high with recyclables: aluminum, copper, car batteries, brass, whatever they can find. a crt tv left out on the curb will have its yoke broken off within an hour or three in order to harvest the copper. neighborhoods sometimes lose phone and internet service for months at a time because someone has recycled the cables. commemorative bronze plaques go missing from cemeteries
but the recyclers are not called aluminieros or bronceros or cobreros, taking the name of their profession from aluminum, brass, or copper; they are instead referred to by the most abundant material they recycle
they are the cartoneros, because what their carts are usually piled high with is cardboard, cartón
> they are the cartoneros, because what their carts are usually piled high with is cardboard, cartón
Paper, or coardboard? It's unclear whether you're referring to cardboard as paper, because after your assertion the only thing possibly linked to it in the rest of the comment is your references to cardboard.
Cardboard is not paper. They share base components, but referring to cardboard as paper is akin to referring to a chair as a board. A chair is made of wood, and may be made of multiple boards, but if we're talking about the qualities and price of boards and you start trying to refute that with the price of chairs, people are going to call you out as losing the thread, rightly so.
For what it's worth, the subsidies I was referring to were the governmental ones in the U.S. where recycling centers and trash services can get funds, tax breaks, or special rates on lending when dealing with recycling which means all recycling done through those trash services are in some part subsidized by the state. At best that usually means you might get your recycling picked up for free or with reduced additional charges, but for the average person in the U.S. paper recycing is not worthwhile at an individual scale. Apparently it pays something around $50-$75 a ton, which isn't nothing, and might be worth doing in some locales, but I have to imagine the logistics of moving material of that weight on a regular basis to where it can be accepted means there are much more lucrative materials to harvest (either it's a long haul for most people, or I imagine middle men accepting it locally and transferring it are going to take a large cut).
mostly cartoneros recycle what the biz refers to as corrugated fiberboard, which most people call cardboard in english. it's made of paper and glue
there are different kinds of paper, which require different recycling streams; cartoneros will accept some others but not all
your talk about 'losing the thread' makes me think you are playing some kind of game where the objective is not to find out what the truth is but to sound convincing even if what you are saying is false
i am not playing that game. as far as i'm concerned, it's up to you to find out the truth, or not, not up to me to shove it down your throat, though i'm happy to provide relevant information
i am aware that in the usa recycling, even fake recycling, is heavily subsidized. that's why i was providing information about what happens in places where subsidies for recycling are scarce to nonexistent. almost nobody recycles plastic here (except for small programs that are subsidized and do things like recycle polypropylene bottlecaps), and only big operators recycle steel. but paper — specifically the kind of paper that corrugated fiberboard is made of — is abundantly recycled; it's not nearly as remunerative as brass, copper, aluminum, or lead, but it's the bread and butter of the cartoneros because people discard it in much higher volumes
i don't think it pays anywhere close to US$75 per tonne though, maybe a tenth of that
> refers to as corrugated fiberboard, which most people call cardboard in english. it's made of paper and glue ... there are different kinds of paper
Isn't that exactly the point I just made? I'm confused as to why you're restating it. In English nobody is going to mistake someone that makes a statement about "paper" as talking about "cardboard", whether they're referring to corrugated fiberboard or plain fiberboard (which are both often referred to as cardboard depending on whether the context is arts, crafts or something else).
> your talk about 'losing the thread' makes me think you are playing some kind of game where the objective is not to find out what the truth is but to sound convincing even if what you are saying is false
If you look at my original comment, what I said about paper is purely an example to illustrate that commonly recycled doesn't necessarily mean worth supporting harvesting for base materials. Many other things go into that assessment (such as whether the base material can be easily separated from other materials and how its cost to transport affect any possible profit that might motivate people to do so.
That you refuted that example by using an entirely different material seems to either be a non-sequitur or misguided. While presented as a counterpoint, it doesn't really seem to affect the claim I was making at all.
That is what I meant by it lost the thread. It didn't really add to the conversation at hand usefully in the way it was presented. If it was presented as an interesting factoid about recycling and cardboard, which is related to paper, that would be one thing, and I would fully support it. But as to whether it means something that can be/is recycled will be scavenged for profit in all cases, I don't think it really says anything one way or the other, and that was what I was trying to convey.
If you're trying to say that paper itself as what any native English speaker would assume we're talking about if they read it, and not just cardboard, is also profitable to recycle and people collect and turn that in for profit then please clarify that point. Otherwise, while an interesting fact, and I'm happy to now know it, I'm not sure it actually affects what I was trying to communicate originally in any way.
corrugated cardboard is made of paper, not an entirely different material; recycling cardboard is recycling paper. at this point i'm starting to question whether you've actually seen a piece of cardboard at some point or whether you're a large language model
certainly it is not the case that something that is commonly recycled will be scavenged for profit in all cases. even gold sometimes escapes recycling
> corrugated cardboard is made of paper, not an entirely different material; recycling cardboard is recycling paper
Did you actually bother to read what I wrote in my various comments? Much of it was devoted to explaining the difference in what it meant and when people say paper compared to what they mean when people say cardboard. Why do you think I talked about boards and chairs?
> at this point i'm starting to question whether you've actually seen a piece of cardboard at some point or whether you're a large language model
I could say the same for you, given your inability to follow what has been said across even a handful of replies.
> certainly it is not the case that something that is commonly recycled will be scavenged for profit in all cases. even gold sometimes escapes recycling
Which also wasn't my point. My point, again and put bluntly, is that some materials may exist in a space where it's not profitable enough to harvest for an individual but they are still recycled either because of subsidies or because efficiencies of scale can be brought to bear by a larger organization, or the combination of the two (subsidies for larger regional trash pickup companies that can also bring economies of scale to bear) which mean a material is recycled, even if not profitable for the common person. Another example would be items that are unlawful to discard of in the trash. There are various chemicals and materials that it's unlawful to dispose of in the trash in the U.S. (motor oil), meaning those items are taken to a recycling and/or disposal center even if there's no payment for doing so.
It's not about it escaping recycling because people miss it, it's about how both economies of scale and subsidies and laws that all go into whether something is recycled which affect that calculus beyond just whether it's profitable, and thus something being commonly recycled is not necessarily an indicator that it's lucrative enough to do so that the material will be harvested by people for profit.
I don't understand how your comment implies a lack of subsidy, it only states that the people harvesting the material can make money off of it. Which would be true if it was subsidized, too.
