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Tuesday, December 9, 2014

Sparkling Sphalerite or "Ruby Jack" or "Black-Jack:" What do you Zinc?

     I've been zincing a lot since last week's PEOTS about Smithsonite or zinc spar. Sphalerite (Zn, Fe)S or zinc sulphide follows next in the zinc mineral series, alphabetically, chemically, and in "sparkliness" or fire. In fact, the red-orange gemmy quality Sphalerite, known to miners as "Ruby Jack," has a dispersion index three times that of diamond:



          Faceted Sphalerite surely rivals Diamond. However, the hardness of only 3.5 to 4.0 (vs. Diamond's 10) makes it too delicate for rings or bracelets. But, wow! What fire!












      Sphalerite comes from a Greek word meaning deceptive or treacherous. When the iron content of Sphalerite is high, it is quite black in color (referred to as "Black-Jack" by miners) causing confusion with Galena or lead ore. Both minerals have similar crystal form; the crystal structure of Sphalerite is akin to Diamond.




          And, in thin section:



       Have you see sphalerite? There are some cool specimens in Franklin, New Jersey, and in the tri-state district of Missouri, Kansas, and Oklahoma.

         Another name for Sphalerite is Blende or Zinc Blende. Etymologically, it refers to "to blind or to deceive," again, from the confusion with lead ore.

    Blend(e)ing right in,
    Steph

        Dispersion of most common gems showing sphalerite (red) significantly higher than diamond (blue). Anatase has the highest dispersion:

    

          Sunrise (not sunset) over Denver. Note the Broncos Stadium, Pepsi Center, and Coors Field all line up on a northeast /southwest line. Colfax Ave heads east-west for miles and miles. Anyone find City Park east of downtown?



       Here is a promo image for the current Denver Art Museum's "Brilliant" exhibit. That lovely yellow gem is likely citrine, a variety of quartz, with a hardness of 7, rather than sphalerite. In the interest of PEOTS research, I may need a trip to the DAM before March, 2015, to confirm.


     

   


46 comments:

  1. So, what the hell is a 'dispersion index', science lady?

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    1. An optical property of sphalerite is its high dispersion of light, almost four time higher than diamond’s (0.156 versus 0.044). In gemology, dispersion is defined as the difference in the refractive index of a mineral at the blue and red light (686.7 nm and 430.8 nm respectively). The dispersion is responsible for the "fire" effect observed in faceted sphalerites and other minerals.

      See chart added above showing sphalerite's high place in dispersion numbers (give me a minute).

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    2. Scientific Steph,

      So, the higher the dispersion, the more "sparkly" the gem?

      Heck, do most women even wear their expensive mega-carat diamond engagement rings? Don't they keep 'em locked away in safes?

      Can one buy a sphalerite ring? How much? Wear it once, lock it away!

      LegoSkinflint(HeyWhatAboutFlintEngagaemetRings?)

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  2. All those cut gems! Looks like someone's putting together a holiday gift wish list!

    Isn't Galena where Ulysses S Grant was from?

    I have been to the Franklin Mineral Museum (in the "Fluorescent Mineral Capital of the World"), but, alas, I don't specifically remember the sphalerite.

    I sought an explanation of the relation between dispersion index and "fire", but all Wikipedia had to offer was:

    "Dispersion is the difference in the refractive index of a material at the B and G (686.7 nm and 430.8 nm) or C and F (656.3 nm and 486.1 nm) Fraunhofer wavelengths."

    Clear as mud. Can you, uh, shed some light?

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    1. Huh! Looks like small minds think alike, too!

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    2. Yes Galena, Illinois for President Grant.

      . . .more later. . .

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    3. This does a pretty good job of describing the analysis of the dispersion of sphalerite via a raytrace study. . .and how too shallow or too deep a cut can minimize that FIRE.

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    4. Something very cat's-whiskerish going on here. Stay tuned.

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    5. Impossible to choose. Great fire either way.

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  3. On another topic, the Wikipedia featured article is on the slow lorises. It must be terrible, being labeled like that. Like all the signs warning motorists about the slow children in my neighborhood. Imagine how they must feel!

    Interestingly (maybe?), slow lorises used to be classified as members of the genus Tardigradus, though they're considerably larger than the tardigrades we discussed here earlier.

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    1. Slow lorises, slow food, slow medicine. . .slow =/ bad ;-).

      It is interesting that they were classified with tardigrades!

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    2. The Tardigradus genus here are the slender lorises, not our microscopic friends of phylum Tardigrada. Also, no relation to the suborder Folivora, which used to be called Tardigrada, the sloths.

      There are a lot of animals out there in no hurry, I guess. Similar, I suppose, to the prevalence (21%) of Kims in Korea. (But by law, last week, only one Jong-un.)

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    3. Of course, I thought maybe you were talking software attack

      Word Woman Jong-un

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    4. Ah, malware. Little threat of extinction among those species.

      Lorises, slow or slender, are cousins of bushbabies (q.v., at 1:26 here). (Nostalgia-inducing extinct corporate logos in that clip.)

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    5. Ah bushbabies/bushmeat have a whole other connotation now in Africa.

      For some reason, the African bushbabies make me think of "The dingo ate your baby" in Australia. The original deal, the Meryl Streep movie, and Elaine in "Seinfeld . . ."

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  4. LeRite Spha. Wasn't he the guy who was in the Hal Shallow movie? Or was he the one who shot Oswald Harvey Lee?

    LambdaLego

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    1. I think your logical error, Lego, is putting Descartes before Dehorse.

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    2. Ché tou, naj.

      I've added a spectacular Denver image and a "Brilliant" DAM image above.

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    3. Ever odd: selling used caskets.

      Ever prescient: Lego.

      Ever green: tree in my house.

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    4. Ever pre-miere scient-ist, Steph,
      What, I’m outta beer. Just call me “No Stroh’s, dammit.”

      jan,
      Regarding the Oswald news story:
      “The coffin sits in storage “at a site in Los Angeles,” said Laura Yntema, the auction manager at Nate D. Sanders Auctions. “It’s in limbo until the case is resolved,” she said.”

      Okay, I’ve heard that some souls of the departed go to limbo, but I didn’t realize their coffins went there also!

      LimboLambda

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    5. Some human souls may go to limbo, but (how low can he go?) according to Pope Francis, All Dogs Go to Heaven. This may be fine with dog lovers like you and Steph, but that bit about Paradise being open to all of God's creatures makes me even more uneasy about the place that I was before. I mean, OK, sure, I can imagine that in heaven the lion will lie down with the lamb (though as Woody Allen has observed, the lamb won't get much sleep), and T rex will be all cozy with us furry mammals (sorry, Mika Brzezinski!), but what about all those obligate human parasites who have gone to meet their Maker? A Paradise that includes malaria, hookworm. syphilis, head lice, etc, doesn't sound all that attractive to me.

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    6. Just the miere-est of overthinking, methinks. Only pets like Noosie and Maizie get to go. (There's a separate heavenly section if you have hookworm or malaria as a pet).

      Having grown up Catholic and being told my cat would not be in heaven by a nun, I was happy to see the Pope being so human and carefully understanding the little boy who lost his dog.

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    7. Pets? I know some serious animal lovers who get very hot and bothered if you refer to their animal companions that way. And, please, no mention of pet owners, for sure. Maybe there are more heavenly sections up there than we first supposed. I guess if you're a seraph, you wouldn't want a cherub moving in next door. Are there zoning laws in heaven? Is it still heaven if there are co-op boards?

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    8. Can there be a Devil's Advocate in heaven?!

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    9. Oh, I sure. It's a seriously honorable role, officially the Promoter of the Faith. We argumentative types are always getting dissed, but without the likes of Christopher Hitchens testifying against the beatification of Mother Teresa, you never know what kind of riffraff will slip through.

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    10. Paul, that was good. Odd twilight zone good.

      I have not seen Black Mirror. . .

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    11. Paul,
      Great TZ link.(p.s.: I am flummoxed b your Dec. 12, 1:19 PM post at Puzzzleria! Wait, Wait, don't tell me! (But a hint would be appreciated.)

      jan,
      Hadn't heard the Woody Allen lion/lamb quip. Thanks. But it is not true! On the warmest, most humid nights, little lion Noosie would crawl on top of LegoLAMBda's torso when he hit the hay. On sub-zero nights she'd crawl under the covers with LegoLAMBda. Never once did he feel threatened. Lego slept like a baby... sheep... after counting them, of course.

      Steph,
      You know your science, and your "parascience." I too truly believe that Noosie is in heaven awaiting my appearance with purrs and open paws. Heaven would be hell without her. (Earth sure is.) But that's exactly my Joseph-Hellerish point. I am not so confident that I am going to get to heaven. And hell will be hell without her too. Not too sure about limbo.

      LegoLambLiesDownWithTheKitten

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    12. Lego, you and Noosie will be together, I'm quite sure. How human is this Pope to show understanding a young boy's hurting heart!

      Paul, I always got creeped out by the Twilight Zone music when I was a kid so almost never watched it. Interesting to see it now.

      jan, a good bunch of riff-raff, as here at PEOTS, can carry us through. . .

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    13. Steph,

      I am no longer a "young boy," but thanks for the compliment anyway.
      Legeezer

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    14. Glad everyone seemed to like Serling's take on "No Exit". Trying to figure out the most economical way to get into Black Mirror. Meanwhile:

      http://the-wanderling.com/mu.html

      https://www.youtube.com/watch?v=yAl2r8PmHB4

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  5. Although Crosswordmanblog presents a captcha, I was able to publish without entering it. Is it because, as Uncle John perhaps suspects, Google recoognizes ME?

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    1. Yes, Paul, I imagine so. . .all the way from St. David to Kennebunkport. . .

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  6. Interesting article about Marie Tharp and the longest geographic feature on earth. I used her (and Heezen's) research in my senior thesis on the Nazca Plate.

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    1. Speaking of Nazca, how's this for a dickish move by a usually admirable group?.

      (Didn't John Kerry memorably say, "Who among us doesn't love Nazca"?)

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    2. Regarding Marie Tharp: Putting DesCartography before DeHorrors of male chauvinism!

      A true hero. Someone should construct a puzzle around her, right, Steph? Is she related to Twyla?

      While reading about Marie’s early dealings with Bruce, I thought, “Heezun idiot.” But then it became clear they became “life partners” and “stone-soul-mates,” so maybe he was not so much of an idiot after all.

      Best line in Brooke Jarvis’s fine story is the last sentence in the paragraph that begins “In late 1952,”…
      “(Heezun’s) earthquake line threaded right through Tharp’s valley.

      That had to be intentional!

      LegoMindInTheGutter

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    3. We await Marie Tharp's appearance in a Puzzleria! puzzle, Lego.

      Yes, I concur, that Tharp story was quite well written and beautifully interwoven on many levels. . .

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    4. Steph, which did you think was "really, really bad"? Greenpeace's vandalism or my Kerry pun? (Of course, when discussing puns, "really, really bad" means "really, really good".)

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    5. The "Who among us..." quote might well have been blurted by Mitt "I love cars!" Romney.

      TalledegoLambda

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    6. jan, the vandalism near the hummingbird Nazca lines site was really, really bad. I know how delicate that surface layer is. They could have easily just photoshopped a message without causing so much long-term harm. (In fact, it looked to me like it was photoshopped.)

      Your pun was really bad.

      "Who among us, indeed, Lego!"

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