[HN Gopher] New mineral davemaoite discovered inside a diamond f...
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       New mineral davemaoite discovered inside a diamond from Earth's
       mantle
        
       Author : pseudolus
       Score  : 72 points
       Date   : 2021-11-13 11:14 UTC (1 days ago)
        
 (HTM) web link (www.newscientist.com)
 (TXT) w3m dump (www.newscientist.com)
        
       | sandgiant wrote:
       | > No one has ever successfully retrieved a high-pressure calcium
       | silicate from the lower mantle before. This is because the high-
       | pressure CaSiO3-perovskite is "unquenchable," meaning that it
       | cannot retain its structure after being removed from its high-
       | pressure environment.
       | 
       | > "When we broke open the diamond, the davemaoite stayed intact
       | for about a second, then we saw it expand and bulge under the
       | microscope and basically turn into glass," says Tschauner.
       | 
       | Science paper (paywalled):
       | https://www.science.org/doi/10.1126/science.abm4742
        
         | kwonkicker wrote:
         | Oh man, they killed the only davemaoite we ever had, it's so
         | sad
        
           | cbozeman wrote:
           | Biologists do this as well. Once we encounter a new species,
           | it's killed and then studied.
           | 
           | This is called a 'voucher specimen'. Obviously it's possible
           | to make a species extinct if you kill the only one of it's
           | kind, and the necessity of voucher specimens is a topic of
           | debate amongst field biologists.
        
           | msrenee wrote:
           | But now that they know where to look for it, I'm pretty sure
           | they'll find more.
        
       | steve_adams_86 wrote:
       | This is fascinating in that if the davemaoite wasn't encased in a
       | diamond, we'd never see it. It came back to the surface in this
       | perfect little package to be discovered.
       | 
       | I wonder how often this happens. Is it normal for minerals to
       | occur inside of other minerals like this? Would davemaoite occur
       | outside of diamonds? Or is it common for diamonds to be imperfect
       | and contain other minerals, but I'm so used to them being
       | advertised and worn in their perfect pure form?
        
         | bozhark wrote:
         | It's rare to have a perfect clarity diamond.
         | 
         | Almost all have some inclusion.
        
           | thaumasiotes wrote:
           | Well, if you're finding the diamond. You can _make_ them as
           | perfect as you want.
        
         | msrenee wrote:
         | It's very normal for minerals to occur inside of other
         | minerals. It's called an inclusion. This can be another mineral
         | or liquid like water or petroleum. It's really cool to see a
         | piece of quartz with a little pocket of water that's been
         | trapped inside for millenia.
         | 
         | It sounds like davemaoiteoccurs outside of diamonds as well,
         | but won't stay stable on the earth's surface without being
         | encased in something which maintains the pressure on it.
        
       | driggs wrote:
       | It makes me sad every time a mineral, chemical, or species is
       | named after some arbitrary human (or worse) because the name is
       | arbitrary, telling you nothing about the thing itself or
       | diagnostic differences from similar things.
       | 
       | It's even worse when the name sounds stupid. "Dave"?! After
       | somebody's nickname, who wasn't even a "David"?!
       | 
       | Thanks for making science even harder!
        
         | capableweb wrote:
         | Names are just names, after a while you'll get used to it. Not
         | sure how you can claim that Ho-Kwang (Dave) Mao was not named
         | "Dave", you get the name you claim to have, so in my mind, Dave
         | is indeed named Dave.
         | 
         | I for one think it's nice that we still pay tribute to people
         | by naming newly discovered things after them, they are
         | immortalized that way.
         | 
         | By the way, the mineral is named davemaoite, both Dave and Mao
         | is from their name, not just "Dave".
        
       | dataflow wrote:
       | > The tiny crystals turned out to be a form of calcium silicate
       | that was theorised to exist in the lower mantle but had never
       | actually been observed before.
       | 
       | So awesome to see theory validated like this!
        
       | shironandon wrote:
       | It feels disappointing that they "cracked it open" but I guess
       | this was for science. Now it has depressurized it would take a
       | significant amount of energy to pressurize davemoaite for
       | exciting experiments similar to those taken to explore superionic
       | ice.
        
         | _Microft wrote:
         | Diamond anvil cells should be able to reach the given pressure
         | (20 GPa?) easily.
         | 
         | https://en.m.wikipedia.org/wiki/Diamond_anvil_cell
        
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       (page generated 2021-11-14 23:00 UTC)