#mincup23 — Public Fediverse posts

Also, the #MinCup23 #zircon victory has been published if you’d like an appetizer while you ready your strategies for #MinCup24! Mineral Cup is coming September 1st!!

https://www.mineralcup.org/about/2023

#Zircon doesn't just keep time; it can record temperature too. The image is of a ~4mm zoned zircon crystal from the Bancroft-area of Ontario (Grenville-age granulite metamorphics). The trenches are 40 and 60 microns wide, created by laser-ablation #ICPMS analyses.

~3.5 parts per million titanium corresponds to crystallization temperatures of ~ 675°C (plus or minus a lot, unfortunately, in this case).
#MinCup23 #metamorphism

#Calcite can form when cool groundwater warms as it rises to the surface. Calcium carbonate exhibits inverse solubility -it's less soluble in warmer water. As a result #tufa deposits can form -like those at Mono Lake. A nice write up of groundwater carbonate deposits at:
https://www.ontariobeneathourfeet.com/flowstone-travertine-and-tufa
#MinCup23 #Ontario #Carbonate #MineralSprings

A contender in this round of #MinCup23, #Calcite comes in several forms, including #Optical Calcite, sometimes called #Iceland Spar or #Iceland Crystal, the strong #birefringence properties are on display in this #photograph as the #crystal creates a small #rainbow-like formation on the right side. This property has made it a candidate for the somewhat mysterious #SunStone from #Viking legend, able to find the Sun despite overcast conditions by looking for the double #refraction.
This form of calcite often cleaves into parallelepiped (parallelogram extended into 3D) sections, such as the one pictured.

Vote in #MinCup23: https://www.mineralcup.org/2023/campaigns/campaigns/campaigns/round-2-match-5

Get a print with this image, or other merchandise at https://heronfox.pixels.com/featured/calcite-specimen-4-heron-and-fox.html

#OpticalCalcite, #IcelandSpar, #Minerology, #VoteCalcite, #Photograph, #MacroPhotography

Currently a competitor in #MinCup23, #Quartz is a #crystalline form of silicon dioxide (#SiO2) with a trigonal #crystal system that, ideally, results in the growth of a hexagonal column with pointed ends, but nature rarely allows this, as this #Macro #image demonstrates.

Vote in #MineralCup23 at https://www.mineralcup.org/2023/campaigns/campaigns/round-2-match-2

Get a print of this image, or other merchandise, at

#QuartzCrystal, #Mineral, #MacroPhotography, #Photograph

#Sapphirine growth at high temperatures can help define the path high pressure eclogite facies rocks take to the surface. Sapphirine forming at point "C" and below helps determine that these samples rose 30 km in the crust (16 to 6 kbar) while only cooling a bit over 100°.

NE #Greenland Caledonides work of Synnøve Elvevold (Norwegian Polar Institute, #Tromsø) and Jane Gilotti (#UIowa) #MinCup23

#Neptunite is one of a few calcium-free titanium silicates (incl. benitoite). Seems like an obscure fact but:

#Zircon includes titanium in its structure, as a function of temperature; this can be a #geothermometer.

To standardize a microbeam analysis (like laser ablation ICPMS), we need a mineral with a known composition, lots of titanium and silica and no calcium, which has an isotope at mass 48. Neptunite and benitoite are perfect for this.

#MinCup23 #ICPMS #chemistry #geology

Blog post by Erin Gibbons explaining the importance of the #Perseverance rover's approach to locations identified as carbonate-rich from instruments in orbit above Mars.
#Mars2020 #McGillUniversity #MinCup23 #calcite #siderite #magnesite

https://mars.nasa.gov/mars2020/mission/status/478/reading-the-rocks-the-importance-of-the-margin-carbonate-unit-on-mars/

limpet teeth, a composite containing #goethite, are the strongest known biological material in tension -twice as strong as spider silk.
#MinCup23 #Limpet #Minerals #Materials
https://daily.jstor.org/worlds-strongest-material-limpet-teeth/

Rumney, R.M.H., Robson, S.C., Kao, A.P. et al. Biomimetic generation of the strongest known biomaterial found in limpet tooth. Nat Commun 13, 3753 (2022). https://doi.org/10.1038/s41467-022-31139-0
Open Access
https://www.nature.com/articles/s41467-022-31139-0

Vote for #stibnite in #MinCup23 because #Antimony Carver from Gunnerkrigg Court https://gunnerkrigg.com is the main character in an amazing #webcomic

So I had to go remind myself what #stibnite is because frankly I'm more used to seeing "antimony" still, but...

as much as #sodalite is fun and pretty... listen, it's not chaos. Stibnite is basically chaos in most of its historical uses, iirc!

Also it often co-occurs with things like #realgar, #cinnabar, #orpiment, and #galena... now that's some fun chaos company. Vote Stibnite for chaos!! #MinCup23

Well done #Cinnabar! It was a tough fight because you are an awesome competitor! #MinCup23

i voted for quartz #MinCup23 #TeamQuartz

You can add your vote for this beautiful & versatile mineral here https://www.mineralcup.org/2023/campaigns/round-1-match-2

#crystals #rockhound #quartz #Hobbies

#quartz is nice and I'm glad for crystal derived time, but I voted #cinnabar. Quartz is omnipresent, but the trip with single digit aged me and my dad and the guide to Obermoschel was unique. I'm working with quartz for clock signals, have some nice oscillators (Rb Controlled, heated) but my picture shows an old russian low frequency quartz bar I'm didn't come around to use yet. #mincup23 #teamquartz

A vote for #cinnabar is a vote for chaos! We're not with the neat and collected #quartz this year! Pah! Live dangerously! #MinCup23

My favorite rock is #BandedIronFormation, a sedimentary rock comprised of thin bands of #Magnetite and #Hematite interlaced with (usually) reddish #jasper (chert #quartz). It's beautiful, primarily down to #TeamQuartz. Sadly, neither hematite or magnetite are in #MinCup23 Vote for quartz here: https://www.mineralcup.org/2023/campaigns/round-1-match-2

@NadWGab #Cinnabar has the exact same symmetry as #quartz ! They are both trigonal with space group 3(1) 2 1 ( @MineralCup cleverness)
They both lack a center of inversion, and they are both piezoelectric.
One could imagine a heavy-metal tolerant species sporting cinnabar-resonator timepieces.
#MinCup23

Still on the fence between #Quartz and #Cinnabar? Did you know that chert is another name for microcrystalline quartz? So is flint (a variety of chert). Flint gave early humans fire, arrow tips, and other tools, it was the first mineral mined, supposedly.
Does #Link go around looking for cinnabar? Is cinnabar featured in #minecraft? Heck no. #MinCup23 #TeamQuartz

Here's a quick fact sheet for match 2 in #MinCup23:

#Cinnabar
HgS
Name: traceable to the Persian zinjifrah likely meaning dragon's blood
Occurrence: low-temperature hydrothermal veins
Neat fact: mined in Neolithic times and used as pigment and to extract mercury

#Quartz
SiO2
Name: possibly of Slavic or German origin (Querklufterz - aren't you glad it got abbreviated)
Occurrence: hydrothermal, igneous and metamorphic rocks, sandstone
Neat fact: piezoelectric

https://www.mineralcup.org/2023/campaigns/round-1-match-2

C'mon folks, go to #MineralCup at https://www.mineralcup.org/2023/campaigns/round-1-match-2 and put your vote in for #Quartz! Quartz is the working stiff of #Minerals, the everyman, it's the Joad family of minerals, basically. Sure #cinnabar is pretty, it's splashy, and is an important mercury ore mineral, it's worthy, but can you count on it when the chips are down and you need to build a road, or make a sandcastle? Why do these people hate #sandcastles? That's like hating #kittens. #MinCup23 #TeamQuartz

Cinnabar in Chinese folklore was associated with the Vermilion Bird of the South, and one of the main ingredients of immortality pills in Chinese alchemy (ironically, since it's toxic, and if you eat it you'll get the opposite of immortal...)

#folklore #cinnabar #MinCup23

A little less than 40 minutes left to go. Which mineral will win? Vote, vote, vote! #MinCup23 #Moissanite #Kaolinite

Just letting everyone know that I voted for #Moissanite in the first round of #MinCup23 mostly because I saw a lot of support for its rival that shall not be named and I'm a contrarian by nature.

Not sure what to vote for in match 1 of #MinCup23? Here's a summary:

#Moissanite
SiC
Name: after Henri Moissan, who discovered it in Canyon Diablo Meteorite
Natural occurrence: as presolar grains in meteorites; in kimberlites (origin: Earth's mantle)
Neat fact: changes color when heated
#Kaolinite
Al2(Si2O5)(OH)4
Name: derived from Gaoling, China
Natural occurrence: widespread weathering product of Al-Si minerals
Neat fact: used in prehistoric times for pottery

https://www.mineralcup.org/2023/campaigns/campaigns/campaigns/campaigns/round-1-match

The slippery slurry is ahead! Have the star stuff fans been snuffed? If you haven’t voted yet, there’s still plenty of time. #MinCup23 #Moissanite #Kaolinte

Vote here: https://www.mineralcup.org/2023/campaigns/campaigns/campaigns/campaigns/round-1-match

Results here: https://www.mineralcup.org/results/round-1-match-1

We have #Moissanite crystals that formed in other stars! Dissolve some meteorites almost completely, and some of the residue is SiC -these grains have carbon and silicon isotopes produced in red giant stars and supernova; from before our solar system formed. See Larry Nittler's (now at Arizona State University #ASU) presentation:
https://www.oca.eu/images/LAGRANGE/EcolesThematiques/Houches_2017/pdf/5a_Presolar_grains_Nittler.pdf
#MinCup23 #Cosmochemistry #Stardust

I used to have a set of #kaolinite dinnerware, but now it's just mullite. #Moissanite can take the heat -up to 2500°C. #MinCup23

@doktrock It’s happening right NOW! #MinCup23 #moissanite #kaolinite

Vote: https://www.mineralcup.org/2023/campaigns/campaigns/campaigns/round-1-match

See Results: https://www.mineralcup.org/results/round-1-match-1

Is it the synthetic form of star stuff, or the slippery, soothing slurry? Make your choice and VOTE NOW! #MinCup23 #moissanite #kaolinite

Vote here: https://www.mineralcup.org/2023/campaigns/campaigns/campaigns/round-1-match

Results here: www.mineralcup.org/results/roun...

The first commercial LEDs were based on synthetic #Moissanite. 3H-SiC was used for yellow LEDs in and 6H-SiC was found to emit blue light. Unfortunately, SiC has an indirect bandgap, therefore nowadays, the more favorable GaN is used, which has a direct band gap and is about 100 times brighter. #MinCup23

I'll start some early campaigning for #Moissanite, because synthetic #Moissanite (SiC) is also super-interesting from a materials science perspective 🤩 #MinCup23

Natural #Moissanite has a huge color variation from green and blue to black depending on composition. It was first identified in 1904 by Henri Moissan in a sample from the Canyon Diablo meteorite found near Barringer Crater.
📷 A Silver - BYU Mineral Specimens 799 USGS Photographic Library

Hooray! @MineralCup is here on Mastodon!

Starting September 1, amazing minerals will go head-to-head in an epic competition to determine which one will join #olivine #garnet #IceMineral #Magnetite #quetzalcoatlite and #fluorite as a #MineralCup champion!

Voting takes place on the Mineral Cup website, but campaigning takes place everywhere, including here. Follow the hashtag #MinCup23 for toots about what makes minerals marvelous.

https://www.mineralcup.org/about