[introduction music]
Hi everyone! Welcome back to Cody's lab.
So, if you remember last summer I went out to Skull Valley looking for meteorites
I'll post a link to that video here. Which you can go check out,
and I came back with this rock here, which we had determined was very possibly a meteorite.
But until now I've not had any actual, you know, analysis done on it.
It was just all visual.
As you know I'm a geology student at Utah State University,
and I've finally gotten the go-ahead to use their equipment to test rocks
and one of the first things I'd like to check out is this one. To determine if it actually is a meteorite.
And, as it turns out today, they're demoing a handheld x-ray device [XRF]
which can get the elemental composition of rocks just by scanning them.
So we're going to go ahead and have that checked out. If this is a meteorite that should show elemental spikes in the iron, nickel, and chrome.
In proportions that you want to wouldn't expect in Earth rocks. if that turns out to be true
then I will go ahead and cut this rock and
thin section it so we can look at it under the polarizing microscope to determine the
minerals that are present and get the actual classification for the meteorite. So, let's go ahead and get started
[handheld instrument makes a noise] Go down. No beam.
Go up. Beam. Go up. No beam. And so if I you see right here. There's no beam.
Right over here. There's no beam. When I tell you this is a collimated beam. It's a beam, okay
That's why we're pointing it at the concrete pillar okay? [students respond] OK.
It's a beam all right
So I'm going to move in. No beam. No beam. No beam. No beam. No beam. No beam. No beam. No beam. I should be getting really close really close,
really close. There's beam!
Okay. So, where my where my fingers are there's actually no beam. [student asks] Is it hitting the thing?
[handheld instrument makes noise]
[student speaking] That is cool! [instructor] Now watch what I move out of it.[instrument stops making noise] [student asks] There's nobody upstairs is there?
No. It's not going through the tile and it's falling off as the distance falls off --
-- so by time it gets to the ceiling it's nothing. Okay? [students respond] Yeah.
Oh, so that's what it's on the screen of the iphone? [instructor speaking] this is aluminium, silica, and that's potassium there's absolutely no calcium.
Calcium [unintelligible] but if you put -- but it's really expensive.
[Cody speaking] So here's this here rock.
[chuckle]
[giggles]
[student speaking] You don't think so?
[students speaking] But do you really want to know? That's right? [instructor] Alright, alright. So, click start.
Alright click on iron and click on nickle.
[wows and chuckles] There it is!
There's this we sure had a lot of fun with that x-ray gun and it turns out
I'm now certified to use one. But now that I'm in my own home
I took the readouts that the XRF gave us and I put arrows pointing to each spike that
corresponds to an element. Since we confirm that it is indeed a meteorite
I guess it's time to cut it and start working on it. So, I'm going to cut it right there
Let's go run it through the saw. This is sped up about 8x because it took a long time to cut.
It's a fairly hard rock, but it looks pretty easy here. There it is you can see metal flakes inside
It looks pretty cool. It's not like any Earth rocks I've seen.
Now to put it on the polishing wheel and grind it down so that I have a very smooth finish.
When I went to go put this in the sink to wash off all the cuttings
I actually dropped it down the sink, and you can see me trying to recover
It here from the s-bend of the pipe. After recovering it from the drain
it's time for some hand polishing. As you can see I'm dumping some 600 grit sand paper onto a glass polishing plate.
I'll over time go smaller and smaller grit to get a very smooth mirror-like finish.
As you can see here. It has to be very flat because this is going to be the surface of rock that I'm actually going to be using for the thin section.
So, while that's drying off,
I'm going to frost the slide so the epoxy will stick. As you can see I've roughed up the glass a little bit so that
the glue will actually have some place to adhere. So, now I put some epoxy on the meteor, some on the slide.
Now glue the meteor to the slide and now I
let the epoxy cure a little bit before putting it in the oven to cure thoroughly overnight.
I also have another slide that I was preparing as well, since, you know, I was in the lab.
Now that the epoxy is thoroughly cured
I put it underneath the reflected light microscope and as you can see there's some flecks of iron nickel alloy as well as other
Interesting grains like chondrules, which are actually precipitated from the solar nebula kind of like interplanetary hailstones.
I think that's pretty cool!
Right now, I'm cutting off most of the rock with the slicing saw. As you can see I just flipped it around there,
so I don't break the glass slide when it finally breaks through the rock.
There it goes.
Looks pretty cool, this very thin, about a millimeter thick. But, it must go even thinner,
so I'm grinding it here with the grinder taking it down to about 0.1 mm.
Which is thin enough that light can begin to pass through it. As you can see when I hold it up to the light.
Look at that nice green color, but it's still way too thick for the microscope.
So, I polish it down by hand even further until I can see through it enough to read.
Now I add on some more epoxy to glue on the coverslip, and there we go.
Once this cures the slides are now completely finished and I can put them in the microscope.
Now I have it under the microscope under plane polarized light. You can see some chondrules here and a lot of opaque minerals. I'm guessing those are metallic sulfides and well metal.
Now under cross polarized light I can see extinctions in the Minerals as I turn the stage.
Some of the minerals that I can immediately identify are olivine and quartz but most of them
Unfortunately are ones that I can't really tell. Maybe there's some people out there that
have a little bit more experience with this. That could identify some of these minerals which you don't find in Earth rocks.
now if the gypsum plate in you can see it's pretty colorful and is pretty nice to look at actually.
And the chondrules really show up nicely. I could just watch this all day!
Kind of like a kaleidoscope. I guess.
Turns out I'm actually the first student to bring a rock into the school and have it turn out to actually be a meteorite.
Let alone thin section one.
I intend to give this piece to the school's geology museum since they helped me so much identify the rock.
As for that other slide that I made that actually came from
my mine project, which will be returning. I now know all the minerals and fossils that it contains.
I'll put in the video of this thin section towards the end card. Anyway. Hope you guys enjoyed. I'll see you next time