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Tuesday, December 2, 2014

Bridgmanite and Smithsonite: One Shocks, the Other Doesn't



          Bridgmanite is the most abundant mineral on earth, comprising 38 percent of earth's volume, primarily in the lower mantle at depths below 400 miles (670 km), but was just recently given a name this year.


         
          
          Bridgmanite is a magnesium iron silicate (Mg,Fe)SiO3 which shows the effect of being shocked by impact as part of a meteorite hitting the earth, as seen in this hand specimen from Australia:


  

          and more pronounced in thin section:


  

        It was named for Percy Bridgman, a Nobel Prize-winning physicist. Before being identified in a meteorite, the mineral was loosely referred to as a silicate perovskite:


          By geologic naming convention, a mineral cannot be named until actually examined in hand specimen (hard to do 400 miles deep). So, American researchers looked at a meteorite sample that had fallen in Australia in 1879 as a likely candidate for sampling material similar to this deep mantle mineral. They used a test that involved the use of a micro-focused X-ray beam in conjunction with electron microscopy. And, thus, a mineral was named in the:


      In contrast to the shocked appearance of bridgmanite, the strikingly smooth, pearly luster of smithsonite, a zinc carbonate, shows the effect of slow, undisturbed crystal growth:


           The crystals often form in grape-like clusters referred to as botryoidal:


          Zinc carbonate or zinc spar (ZnCO3) or smithsonite, was named after James Smithson, the same chemist and geologist who donated money for the Smithsonian Institution. Smithsonite has a hardness of 4.5 and a specific gravity of 4.4 - 4.5. In addition to the green, and blue-green colors, it also occurs in lustrous, pearly pink crystals:


       Though you may have guessed my favorite, the blue botryoidal, smithsonite clusters:


     How about you? Were you shocked to learn bridgmanite was only recently named? That smithsonite occurs in so many pearly, lustrous, botryoidal forms and in so many colors?

Looking forward to your often shocked and shocking comments (as well as your pearly luster),

Steph

45 comments:

  1. Okay, I’ll say it first: It figures that a Smithie would be partial to Smithsonite!

    Poor brigmanite. Its subtly sublime (there must be some lime in the upper mantle or transition zone, right Steph?) brilliance lies buried hidden beneath the bushel basket of the earth’s crust. While that primadonna – pearly, lustrous, botryoidal, sapphiresque smithsonite – preens smugly upon the surface like some holier-than-thou Holly-go-lamplightly!

    Smithsonite: all rainbow hues including blues
    Brigmanite: down in the dumps with the Subterranean Homesick Blues

    Smithsonite: Sounds like luggage filled with anvils!
    Everyone called my grandfather “Brig,” I am told.

    LegoLamBrigman

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    1. Yes, the Smithie connection is a part of the allure of Smithsonite, Lego.

      Indeed, since Bridgmanite contains Mg (magnesium), an alkaline earth metal, the mantle is partly limey.

      Enjoyed the video clip; the singer/guitar antics man reminds me of Prince Harry.

      "A suitcase full of anvils:" perfect description of impedimenta!

      Head to Sir Brig without heading to THE Brig. . .

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  2. Yes, I'd say it's shocking that Bridgmanite went so long without a name.

    Love the term botryoidal, which shows up sometimes in medicine. Shares an etymology with the "Noble rot", Botrytis cinerea, which benevolently attacks wine grapes, poking tiny holes in their skins, causing them to partially raisin, essential to the production of sweet dessert wines. Which leads to the wonderful German classifications of same, in order of increasing botrytisation, of Sp├Ątlese ("late harvest"), Auslese ("selected harvest"), Beerenauslese ("selected harvest of berries"), and, finally, Trockenbeerenauslese ("selected harvest of dried berries"). (I also love how German lets you string together a wholebunchofwordswithaverbattheend, saving on all those expensive empty spaces.)

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    1. And think of all the ink saved on commas!

      I, too, like the term botryoidal. Think of all the early classified ads looking for a person to be a Botryoidal Holder for royalty. . .

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    2. And for those who publish electronically, fewer dead electrons.

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    3. When I was a young limerick out-cranker, I wrote an effort that went something like this:

      Silly Polly thinks long words are bliss.
      In her poems all short words she’ll dismiss.
      If she thinks them too short
      As a final resort
      Shewillrunthemtogetherlikethis.

      Lego No Fan Of Inner Space Lambda

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    4. David, does an electron escape a published electronic text via an egress? ;-)

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    5. This may be an old chestnut story with which most PEOTS followers are familiar, but maybe a few haven't heard it:

      P.T. Barnum, it is said, once filled an exhibit tent with curiosities, wonders, rarities, freaks of nature and exotic creatures. People lined up around the block to pay the required admission to enter the tent (which could accommodate only a limited number people at a time) and be wowed by the exhibits within.

      When Barnum, who continuously monitored the circulation of the patronage inside and outside the tent, noticed that gawkers were lingering a tad too long inside, he tacked a sign above one of the exits (which looked as if it might be a entrance into an area filled with even more exhibits).

      The sign read, "This way to the Egress!"

      LegoSuckerBornEveryNanosecond

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    6. You say egress, I say egrets.

      Rosanne Rosanna Dana (sure miss Gilda)

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    7. Scientific Steph,
      Gilda. Golden. Agreed.

      In this wake of Thanksgiving let’s be grateful for the gifts she shared, albeit not the cornucopia had she lived longer. Probably the best way to make sense of any premature loss of life is to be grateful for any gift of life and love, no matter how short-lived.

      So, no {r}egrets, just gratitude…
      (If you liked this Tom Rush song, check out his version of the Jackson Brown-penned Shadow Dream Song. A great talent.)

      LegoStillMournfulYetGratefulStill

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  3. Thanks for the clips, Lego. Way to get the morning rolling. Well, the tunes and the incredible launch of Orion just now.

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    1. OK, you know I'm as much of a spaceflight geek as anyone. But as a scientist (by philosophy) and a taxpayer, I've gotta ask whether this back-to-the-60's approach is really the best we can do? The science per buck return is so much higher on unmanned space probes. NASA seems intent on selling the whole Orion program by dangling the carrot of a manned trip to Mars, but so many questions of radiation exposure, medical/psychological effects of long-duration isolation, and the logistics of bringing enough consumables out that far, remain wide open. What's really driving the program? Is this where we want our science budget spent, or is it being pushed only by bureaucratic and aerospace corporate interests?

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    2. (But, yes, I watch the liftoff live, and will probably watch the splashdown, too. With less enthusiasm than in 1969, tho.)

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    3. Valid points, all. Yet, I did feel a thrill akin to 1969 this morning. . .Great to see the splashdown was so close to target.

      It is likely way too much money with way too much risk--absolutely.

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    4. At the risk of sounding like Woody Allen ("The food at this place is really terrible... And such small portions.") it's also disheartening to consider the planned course of the Orion program. Your next opportunity for a splashdown thrill won't come for another 4 years, and that will also be an unmanned flight. The earliest manned flight won't be before 2021 (with an as-yet undesigned booster), and no one really has any idea what the mission might be. Meanwhile, unless SpaceX's Dragon V2 (there's an unfortunate designation for rocketry history buffs!) pans out, we'll still be bumming rides from Russia (using their nearly 50 year old Soyuz) to get crews to the ISS.

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    5. Wow, 2021 isn't that far off! My daughter graduates from college in 2015 and that seemed w a y in the future. . .And now in 6 months we'll be cheering her on. It'll be here before you know it.

      On another front, I am now getting ads here for "Barefoot Writers." Maybe a bw might hitch a space ride in 2021?!

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    6. Comforting to know other brains work similarly. . .

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    7. Discomforting to think other brains might work dis·sim·i·lar-ly?

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    8. Rosejan Rosejannajanna!
      Legildo...

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    9. LOL, Lego. The most carefully written name at PEOTS . . .;-)

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  4. Replies
    1. Now, ads for Scotsmen Ice Machines. I am so easily amused. Off to enjoy Indian food. What wondrous ads will appear later tonight?! ;-)

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  5. Replies
    1. Seems like a pretty vague concept. Of course, one of the arguments in favor of lower-cost physician extenders like PAs and NPs is that they can spend more time with patients than high-price docs. But the health care reimbursement system we have, like most productivity-based pricing regimens, pays more for more patient contacts per hour, for both doctors and mid-levels. Slow food may taste better than fast, but it also costs more. Do we want to continue to encourage boutique care for haves, and less-than-optimal care for have-nots?

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    2. Agreed. It is pretty vague.

      My friend went to an oncologist and described wanting to get checked out since both her mom and aunt had died of breast cancer at a young age. The dr., looking at his computer screen, clearly focused on that only, and said "OK, is there any history of breast cancer in your family?" She found a new doc.

      That felt like "fast medicine." Well, and really poor listening.

      My dr friend does most of her charting on the weekend. She feels she can't really listen to her patients and diagnose if she is documenting things in the office.

      She is also really annoyed because if a patient won't have a mammogram, PSA test, pap smear, or other routine test she is "docked."

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    3. Yeah, "fast medicine" and poor listening are two sides of the same coin.

      At least as far as Medicare is concerned, they're happy as long as you document that you document that the right questions were asked and the right care offered. The patient always has the right to refuse, but you're not penalized as long as you try to do the right thing.

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  6. Any idea what happened to the Blaineville site?

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    1. Bizarre. Maybe the giveaway clue crashed the site.

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    2. Maybe the North Koreans are after our lapel pins.

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    3. Hmmm... looks like the captcha service is off on this blog site, too.

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    4. ... and now we probably can't even get away with waterboarding captcha'd hackers.

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    5. Hmmmmm, definitely strange goings on in the interwebs today. You (1) and Lego (2) may surrender your pins perhaps. I am still awaiting mine.

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    6. Poor baby! After my second pin, I'm definitely telling Will to call you instead. I only ever wear two lapels at a time, after all.

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    7. Looks like the threat of enhanced interrogation techniques did the trick. Blaine's back up.

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    8. Waah. Do you actually wear yours? As in every day?

      Giveaway clue still over there. . .

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    9. Tucson Mineral Show ads now at PEOTS. I've heard it is phenomenal for rock hounds.

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    10. Nah, I've only worn it once, to lunch with a couple of old Bell Labs friends, who had to put up with many years of griping about not being called, It's very tiny, and hard for elderly eyes to read.

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    11. My niece hennaed several guests when she was with us around Thanksgiving. I told her next time we're together, she can do a larger version of the lapel pin on my biceps.

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    12. Whew! I was afraid Blaine was blocking me. And there's no captcha at Puzzleria, either. I think it's a Google thing. Let's face it -- it's ALL a Google thing.

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    13. I have not been hennaed. Do you need good penmanship?

      The captcha thing is quite odd. . .

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    14. It appears that a steady hand, artistic eye, and lots of patience are all required. Way beyond my abilities. (I have polished my wife's nails a couple of times over the past 30-something years, during nail emergencies. Not sure if she appreciates my comparison to painting model rockets.)

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    15. I was surprised to see henna can last a couple of months. And black henna can be permanent on some skin types.

      As to nail painting your wife, well, the things we do for love! :-)

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