Welcome back to the shop everybody!
So, in today's video we're going to be trying to identify a rock: this rock.
And uh, I'll throw a photo in right here,
both sides of it so that you can very easily see what I see.
It's much nicer to look at a rock in a high quality photo out in the sun.
So, we are going to go through my steps that I use to identify rock.
This is something that I haven't seen really covered
hardly at all on any rockhounding YouTube channel.
So I'm going to start off here and let me say I'm by no means an expert in this.
Uh, I'm not like a geologist. I don't have a degree in this stuff.
But uh, as you can maybe see back there I do like rocks a lot.
Um, so we're gonna kind of go through uh my step-by-step process on trying to figure out
what a rock is, and uh you know if you think I'm screwing up, uh go ahead and let me know.
I like learning new things as well.
So um, I have written down here um in
no particular order the things that we're going to try to identify about this:
the area of origin; is it magnetic; the hardness; metallic; the specific gravity of it;
the luster and the color, and hopefully by the time we get to the bottom
of this we can look at this as a bigger picture and have a proper identification of this rock.
So let's start with uh with the origin.
Um, I know that, well, I picked up this rock myself, so uh southeast Oregon.
Southeast Oregon is the origin. Um, if you do not know the origin of a rock
that just makes it more difficult and you're going to want to try to figure that out.
You know, one of the things that you often see on places like Facebook is
people post a photo of their rock and they have no idea where it came from.
Often times uh you know where it came from? It came from a rock shop,
um and it's often, well not often, it could be dyed,
um and it's probably from some far off land where some exotic material came from.
Other times you know um it's just a random rock. Anyways that's neither here nor there.
So uh, southeast Oregon. Is it magnetic? Um, I do have a I have a bunch of magnets.
Let's use this guy right here. How about this magnet? Boom! Check that out.
Not magnetic. This is with a rare earth magnet.
So there's that. Um, let's get that out frame. Not magnetic, so put down no.
Um, is it metallic? So, you know, does something have a metally sheen to it?
Could it be um have like a zinc in it, a lead?
Um, obviously is it just you know some type of ore whatsoever?
No um, this is not megneti.... This is not metallic so, but uh we'll put no for that one.
Knock off the easy ones, right? Um, let's see what's next. Let's do the hardness.
So this is something that comes up often and maybe you have seen this image.
Uh, and it's just a kind of a little bit of a breakdown of
a hardness testing kit that you can put together yourself.
Um, well I have a proper hardness kit right there.
And uh, in this process we are going to probably want to use any reference
material that you would have. So, in this case we use the rocks and minerals book.
These books are okay but they are not going to be as useful as this.
And then obviously if you have a more region specific book like
you know we know that it came from southeast Oregon so here's one that is specific.
So what does, let's slide these aside for right now. Okay, hardness.
Um, this is the deluxe hardness pick set from Mineral Labs. Um, I like this.
Uh, you don't have to get this one but this little like plastic field case one is more awesomer.
Um, man I should uh work on my engrish.
Uh, but anyways you can see it comes with uh harness picks and then it also comes with
a little piece of glass, a little white streak plate, a piece of aluminum,
piece of uh brass, so 2.5, 3.5 and then it comes with a little sharpening stone
for your picks and kind of a well not so great uh little magnet here.
This little guy, a little magnet, to be able to test uh if things are magnetic.
I, I kind of really prefer the bigger rare earth magnet and I'm not gonna
go super in depth here but it does come with some instructions on how to actually do a hardness test
and then it comes with a how you sharpen them and
then a high low or minimum maximum range for some more common minerals.
So this is a nice little chart to have. You know, you can always just write,
write down in your notebook uh or whatever you know uh look it up on your phone.
So um, I have a feeling um that I know what this is but let's just start out and we're going to
work our way through 1 through 9 and we will see at what point we can produce a scratch on this.
So, hardness is essentially um the ability for one thing to scratch another thing.
And uh, I'm not gonna bore you with all the details but a guy back in ye olden days
came up with a list of ten minerals and it's like softest to hardest
and you know each each one can scratch the other one type, type of a deal.
Um, you know people have covered that here on YouTube, I'm not gonna waste your time.
Go to Wikipedia you know. Um anyways, so let's just go through here.
Um, when you do this, I'm not gonna do the 2 and 3 I mean I...
Something that's 2 and 3 like you can just do it with like your fingers, right?
Like you can easily scratch um stuff generally. Generally speaking it's a very soft material.
I can just feel from feeling enough rocks that this is a much harder material
so uh we're gonna be starting off with a 6.
And the way you do this is on a nice smooth part of the rock, which this has a lot of,
you're going to hold this and kind of like how you would uh you know write with a
with a pen, right? And uh try to put in a little scratch.
So that did nothing and that is the 6.
So, I can kind of feel by dragging my fingernail over the area that there is no mark.
You want to use your fingernail looking for that
scratch and not just your eyes. So we will bump it up to the 7.
And once again I feel nothing, so this is over a 7.
Which, that is impressive. I was not expecting that. Let's do the 8.
That definitely left a scratch. I can uh both see it and I can feel it.
So we are...we know that we are between a 7 and an 8. So we'll put a hardness of 7.5 for right now.
7.5. Um you know uh, there are things that you can kind of find, rock-wise,
that if you have a pure example of it, you can find something like, you know, a zircon,
which is generally a 7.5 if it's a pure zircon. I don't have any so we're just going to go with 7.5.
We're rounding, right? Um, that's that okay. So uh, let's see. Yeah, Oregon...
Okay so, now let's talk about the specific gravity and then we're going to go through...
Well actually let's do this. So let's do this, let's go through our books now
because I understand that some of the other stuff might be a little more difficult for some people.
So let's put this guy away.
Um, you can use books just like these to do some general rock identification.
So, in this, I already have some stuff bookmarked, we have some general mineral identification here.
Which, this can certainly help in some aspects of it.
Uh, you know you have like the mineral, the hardness, uh wait no...yeah,
you have kind of a general hardness categorization on the blue columns.
Um, you know you have your cleavage, you have your fracture, those types of things.
You can kind of go through here now. And we know, we know right, that it's a 7.5.
So uh, what are some of the things
that are in that 7 plus category here? So that extends, no it's just that.
So um, what could this possibly be out of this?
Um, I know it's probably too small for for you to read there.
Um, if I had to guess um based on the characteristics of it:
the cleavage, the fracture, um I would go with uh chalcedony.
Now, you know I'm sure some people are like whoa whoa whoa uh uh chalcedony is always like a clear,
or like an opaque or like you know some type of agate-y material. And that's not true.
That's not true. So let's um let's flip it around in here.
Um this also has a rock identification key in it, which this can be very helpful.
So I'm not going to go through and read all of this.
You can buy this book on Amazon, go read it yourself, right?
So uh, igneous, metamorphic, sedimentary.
Well that would probably be more likely to be a sedimentary rock in my opinion.
You know, this is not a pure thing. So uh let's go through and uh we can follow along
these whole all of these steps here.
Um, we're not going to be doing that for the sake of time in this video.
I have already bookmarked the two options for this and that would be chalcedony and
that would be would be, uh chert.
Um so, chert and jasper, whatever it's chalcedony. It's all basically the same
thing, uh it's a variation of silica, essentially.
Um, so this is one thing that you can use to help identify stuff
and then of course if you can get more region specific, um all the better.
We're going to now do the specific gravity.
Every rock/mineral has a specific gravity. So, to start this you're going to need some stuff.
You need some water; some string: uh thread, floss; the sample; and a bowl.
So uh, this is just kind of your average type kitchen scale.
In the perfect world you'd have a fancy lab setup but this is practical rock identification here.
You're gonna set that to grams, throw that guy on there. So uh you know preferably go more accurate
but we're going to write down our dry weight which is 112.5. And then uh,
we're gonna take some uh take some floss here, probably too much, and uh well give me a sec.
I gotta tie this on here so it can dingle dangle and I will turn the camera back on.
Hey! I did it and that only took me several minutes.
So now you have your sample that can hang just like that.
I'm going to throw
that on there. We're going to add enough water to be able to fully submerge the thing.
That's definitely good there. Then you're going to zero out your scale.
Now um, we're gonna dangle this in in the water.
And uh you know, don't touch any of the sides or anything like that.
And you want it fully submerged just right under the surface.
So let's go with 40...45. I think 45 is good. Alright, so we have our displacement weight of 45.
So then you take your dry weight and you're going to divide it by your displaced weight.
So, 112.5, well trust me I know how to use a calculator I've done it before, 112.5...
112.5 divided by 45 equals 2.5 so the result of that test is 2.5 for the specific gravity.
Now, I wrote down some examples of things that we have already deduced that it could be:
chert, jasper, chalcedony.
We're out of the chalcedony category and we are in the chert and jasper categories.
So, a couple things to factor in here. If your sample is not pure,
meaning um you know there could be an air pocket inside it, a little little void,
other minerals, it will give you an off reading.
Um you know, something like a pure piece of quartz crystal would be a great example of something that
could be flaw, flaw free or flawless even. Um alright let's uh, let me put all this stuff away.
So, the next thing on our list here is going to be the luster of the rock.
Now this, that side's a little wet still. Luster is difficult.
Color is also difficult because it's in the eye of the beholder for the most part.
So, luster refers to how light interacts with it. Um you know, you can be like earthy,
silky, glossy, waxy. I would say this has a waxy to silky kind of luster.
So I'm to go with waxy on this and then uh we can talk about color. Wax!
Um okay, so color is also deceptive. Uh, it is really um in the eye of the beholder and then also
whatever the background is that you're looking at um will affect, affect that.
So, in that case things like this are used: streak plates. So what is a streak plate?
It is a piece of ceramic tile, no, no glaze on it and uh you want to take a
light colored rock like this and scratch the dark one and vice versa for the white one.
So, pick a part that you can do this and uh,
that.
So um, what color is this rock? Are you thinking it's brown?
I'm going with a light brown on that I know it's not going to really
show here, that's very difficult.
And then you know, obviously these are washable you can usually just rub it off with your finger.
So we're going to go with a light brown on on that. Light brown!
Okay what's next, what else we got? Is that it, is that everything?
Okay, so based on what we know here and what we are able to look up in these,
let's go back and look at page 246, I believe, in here. I lost my bookmark.
Sure um I'm gonna, I'm gonna say no on the chert based on everything that we can uh observe.
Oh, grain shape! Grain shape, I totally forgot. You're gonna want a
jeweler's loupe, and uh this just allows you to have nice magnification.
And you can look through and you can see, see things that you can't see with your naked eye.
Obviously if you had a microscope that would be ideal. Um, so where are we at?
Oh the grain. Let's put down the grain.
Grain. Boom!
Um, now this book here,
lists the grain shape as crystalline for chert and
concoidal for jasper.
So that's another key factor here. Is this crystalline or concoidal?
Now, based on the way this is fractured I'm going to go with the concoidal.
So, I know that from searching, jasper does come from southeast Oregon, it's not magnetic,
6.5 to 7 is generally the range in which jasper falls hardness-wise so this is a
little bit of an outlier at 7.5, but that is still an acceptable number.
Um, it's not metallic, uh it falls within the specific
gravity of jasper, and as a waxy luster like jasper.
Jasper has, does come in light brown and this has a concoidal grain structure
which jasper does, therefore I'm calling it jasper.
So, if you followed along with all of that um that's how I go about identifying rocks.
Maybe I missed some things. Maybe uh you're laughing at my inability to speak or
work a calculator and that's totally fine.
And uh yeah, I hope that that helps you. Uh, I'll put some links down below to
different stuff if you want to buy some of these things, I guess.
Um, and as always um thanks for the views and hitting the subscribe button.
Boom. Do that and uh I'll catch you on the next video!