Basically, all legal free speech is allowed. We will assist the authorities in dealing with illegal speech. You are each other’s moderators. Have fun. And don’t forget to MAGA at nuclear levels.
Citizen U
Day 77 – IRIDIUM.
OPEN THREAD 20200122
Published
The U Tree 
Iridium is essentially everything that osmium is — just slightly less so. It’s the second densest metal, it’s got another hilariously high melting point (almost like osmium’s), it’s ridiculously strong, right behind osmium……however, it is actually MORE corrosion resistant than osmium.
It is named after Iris, the goddess of the rainbow, because its salts have a wide variety of beautiful hues. Mind you, getting it to react to anything so that you can see such colors is such a pain that it’s nice to have a payoff.
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A lot of what is to be said about iridium was covered yesterday, when I talked about its near twin, osmium.
Osmium has a slight blue tinge, iridium might have a very slight yellow cast (less than cesium and certainly less than gold). Iridium is very slightly less dense. And it’s probably the least reactive stuff known, the noblest metal.
Because it is (relatively) concentrated in metal cores of planets and iron nickel asteroids, iridium turned out to be the smoke coming out of the gun that killed almost all the dinosaurs (birds are, essentially, the dinosaurs that didn’t get whacked). A thin layer of clay directly on the Cretaceous/Tertiary boundary in rocks was found to contain larger than normal concentrations of iridium, and that makes it the smoke coming from the gun; the gun is a big asteroid strike, perhaps a 10Km lump of metal that fell in what is today just offshore of Yucatan. The fires, sulfur dioxide, and dust from that wiped out essentially any large lifeforms leaving behind smaller birds, mammals, amphibians and reptiles on land (and of course insects). But the big, non-avian dinosaurs were toast. In many cases quite literally.
Also here’s a charming video talking about a professor’s trip to a PGM refinery.
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That is a really cool video, but it would have been even cooler if he’d swung that bar through something made of sheetmetal.
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An interesting little side note involves iridium and Chicxulub.
Many paleontologists had noted that there was a major difference between fossils of the Cretaceous Period and what is now known as the Paleogene Period (which was referred to as the Tertiary Period when they were noting it). This was about 66 million years ago and was essentially the extinction of the dinosaurs. And right at that boundary, there was this peculiar layer of clay….not very thick….but oddly rich in iridium.
Luis Alvarez and his group proposed an extraterrestrial origin for this iridium in 1980 — not that terribly long ago. And, indeed, evidence has grown that an asteroid about 10 kilometers in diameter (about the size of Manhattan) landed just north of the Yucatan Peninsula at about the right time, creating a crater named Chicxulub.
OTOH, there are some who claim that the mass extinctions were the result of the Deccan Traps, which also sound cosmically horrid…….or the Shiva crater, the Boltysh crater, or the Silverpit crater. One of the first things in the development of time-travel tourism will be to lock-out that area to accredited investigators only with liability waivers.
https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene_boundary
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Then, again, it’s possible that the asteroid that created the crater off of Mexico went entirely through the earth, melting along the way and possibly scooping up additional iridium from the core, before getting erupted all over India. It’s sort of like the ancient Chinese curse: “may you live in interesting times.”
For a much, much, much smaller version of this sort of thing, there’s the eruption of Mount Mazama that created Crater Lake in Oregon. This was a single volcano about 12,000 feet tall that exhausted its magma chamber and collapsed about 7,700 years ago, ending up 8,157 feet tall with a 2,000 foot hole in the middle. Thing is, there were people around when this was taking place, and ancient oral histories document the sense of awe, wonder, and sheer terror involved
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The ash from this eruption covers about 350,000 square miles. https://en.wikipedia.org/wiki/Mazama_Member . It’s orange-ish.
And that’s from one volcano, one event. No asteroid required.
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Another little digression….
Everyone knows that water boils at 212F. And when you put it in a kettle, it more or less does. But if you put it in a vessel that pressurizes to 10 psi — which is not a lot — the boiling point goes up to 239F. Commercial air compressors run at 100-150 psi — to get the equivalent pressure of dry steam, you’re running 337F-365F. Inside the boiler, you have a whole lot of 350-degree water, but the steam pressure forces it to stay in liquid form, and you can bleed 125 psi steam off all the time.
But if you ever get a tiny crack, or a rivet failure, or valve damage, the pressure in the boiler can drop, while the temperature of the water does not. In such cases, the heated water will generate more steam to go through that little crack or flaw, which might open it further. In extreme cases, most of the water inside the boiler will turn into steam (“flash”) and the boiler will essentially turn inside-out through the hole. Mind you, this happens much faster than you can sit beside and take handwritten notes. That’s why all commercial boilers need periodic inspection and steam locomotive wrecks could be horrific. The chain-reaction nature of so much super-heated water is very dangerous.
And that’s why Mount Mazama’s last eruption was so spectacular. Its magma chamber had so much material that had been heated beyond its boiling point — but was kept liquid because of the extreme pressure that it was under — that it flew out of the volcano when the pressure was released. That’s why Mazama Ash can be found in so many states and provinces — the release of pressure caused more materials to boil off in an instant, propelling more material out of the magma chamber.
This is also why various volcanoes have their lava fountains and columns of ash — trapped materials that are above their boiling point at regular pressures are under higher pressures encased in molten rock. When the rock approaches the surface, they turn to gas and propel lava skyward.
And once those “volatile” materials were gone, there was nothing left to hold up the mountain.
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There are spots where flowing gooey lava had coated a slope of Mount Mazama and started to cool and solidify — and when the center of the mountain collapsed, it started to flow backward into the crater.
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Vaporizing minerals is one heck of a scary heat concept.
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Just among elements, Arsenic, Cadmium, Cesium, Magnesium, Mercury, Phosphorous (white), Rubidium, Selenium, Sodium, Sulfur, Tellurium, and Zinc boil at 1137, 1413, 1240, 1994, 675, 531, 1270, 1292, 1623, 823, 1810, and 1670 respectively. They could all be superheated inside a volcano and emerge as an expanding gas.
Remember also that the source of the Cascades is the Juan de Fuca Plate being subsumed under the North American Plate. Anything on the Juan de Fuca Plate gets shoved into the earth’s mantle and — if light enough, bubbles up into magma. It can have all sorts of things forced into solution at tremendous temperatures and pressures.
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Entirely through the earth?
Sorry, for an asteroid traveling a few tens of kilometer a second I call bullshit. It’s just not going to plow through thousands of miles of dense rock and iron, not even molten iron–the viscosity will bring it to a halt long before that. And of course the energy of impact will itself vaporize quite a bit of it.
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Iridium production tends to be about 3 tonnes per year, with an equivalent use, and runs about $400-$500 per troy ounce — however, the same situation as with osmium’s Haber Process follies can occur with Iridium as well. Semiconductor manufacturers juiced it up to over $1000/ounce 2010-2014.
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OK……let’s see……here we go —
Everybody knows the fourth movement of Beethoven’s Ninth Symphony…..this is the second movement, the Scherzo.
A scherzo is defined to be a piece of a light or playful character, often inserted in place of a minuet.
Given my long-standing association between classical music and cartoons, I find its quieter moments remind me of playful mice — which soon attract loud men and terriers to look for them, banging furniture around with the kettle-drums. The orchestration is particularly beautiful, in the way the woodwinds will back the strings, then the horns will back the woodwinds, and so on around the pit.
When this piece was first heard by the public, Beethoven was almost entirely deaf. His friends physically turned him around to see the applause.
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I also like how the conductor dispenses with the BS that he is controlling the orchestra in real time. They’ve drilled this thing for WEEKS, and if the individual players didn’t get it then, they’re not getting it now. At this point, he’s mostly a cheerleader.
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True. The conductor has done all of his work BEFORE the performance, getting the orchestra to play it the way he wants it played.
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An American orchestra had just arrived in Europe for a two-week tour. One hour before the first concert, the conductor became very ill and was unable to conduct, and the orchestra suddenly had to find a substitute. The orchestra manager asked everyone in the orchestra whether they could step in and conduct, and the only person who was willing was the last chair cellist.
The manager was very nervous about this. “We can’t audition you,” he said.
“No problem,” replied the cellist.
“There’s no time to rehearse. You’ll have to do the concert cold.”
“I know. It’ll be all right.”
The cellist conducted the concert and it was a smashing success. Since the conductor remained ill for the duration of the tour, the cellist conducted all of the concerts, getting rave reviews and standing ovations at each one.
At the next rehearsal, the conductor had recovered, and the cellist took his place at the back of the cello section. As he sat down, his stand partner asked him “Where’ve you *been* for the last two weeks?”
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A man went into a novelty shop and saw an item that caught his fancy almost immediately. It was a stuffed rat. The man couldn’t take his eyes off it, and finally asked how much it cost. The answer was “$79.95, but if you buy it, you can’t return it for any reason.” The man thought this was a bit odd, but he was really taken by the stuffed rat so he bought it.
As he headed down the street with the stuffed rat, several live rats started following him. He thought this was really odd, but he kept walking. Within a few blocks, he had a huge pack of rats behind him, and some were closing in from the cross streets. When he got to the river at the center of town, he threw the stuffed rat into the river, and all the live rats jumped into the river and drowned.
The man returned to the shop. As soon as he walked in, the owner said “I told you you couldn’t return the stuffed rat!”
The man said “Oh, no — I don’t want to return it. I was wondering if you had any stuffed Antifa….”
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LMAO!!! Oh, that’s good!!!
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I saw this …. UN telling the US what we can and can’t do.
Immediate response thought was an unladylike FU in a Ron White voice so I post that here v. wqtree.
Some of us quiet Southern ladies have some deep redneck roots that date back to Scotch, Scotch Irish and Irish blood of Rev War, Overmountain men, pioneer stock and it comes right on out if provoke enough
https://www.thegatewaypundit.com/2020/01/un-human-rights-ruling-says-climate-refugees-cannot-be-returned-back-to-their-home-country-us-must-offer-home-to-all-central-americans/
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Let them enforce it! grrrrr…..
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