Hey everyone, my son-in-law David's with me today
Hello!
We're heading to a beach I can't tell you about because
recently, a few weeks ago I was out on the beach, I met some people, and they
told me about their secret beach, but there were threats involved if I told
the internet where it was, so
it's Lake Huron, I'll just say that.
(waves crashing)
I've got some ice, but it looks like if we get in the water we'll be all set, we just
won't be hunting up on the beach too much
just spotted my first petoskey stone
that's not a bad one
well, it looks like we've got the beach to ourself; it's Christmas eve
and my daughter is at her grandmother's house for Christmas tea, which is a
tradition she's done since she was a little baby.
That's a pretty rock (David) Yeah
So David, you went to Christmas tea, what, two years?
(David) Yeah
So I've never actually been to Christmas tea, so you're
you're one up on me
but uh, baby Joseph gets to go this year
(David) Yeah, I offered to bring him along with us, but for some reason they
(David) wouldn't let us take him. I can't imagine why.
(Rob) [laughs] we could have thrown him in a backpack.
(David) Yeah!
There's a gowganda tillite
It's an old rock. 2.2 billion years old, from what I've read.
(David) Wow.
Is that a puddingstone?
It's kind of like that one you just picked up, but
I guess - I guess that's a puddingstone, I'm not sure.
Weird looking one. Ooh, here's a pretty green rock.
That's a cool looking rock. It's nice
That's a fossil-y one. (David) Yup
There's a horn coral in there (David) yeah, nice rugose coral
(David) a lot of coral. (Rob) Yeah
I always go for the bright colors. (David) Yeah
I don't know what kind of rock that is (David) That's pretty
(David) Yeah, hard to tell (Rob) Another one with the crinoids in it
(Rob) got white (David) Yup
(Rob) What's the back look like? Nothing. Eh, a little bit. Not as much contrast
(David) It's like some other shell-y, yeah (Rob) some popped out
(David) Brachiopod or something
Check out the frozen sand on top of the ice, like the patterns it makes
(waves crashing)
Kind of interesting patterns in that, oops!
I'll just throw it back.
(David) Yeah looks kinda gneiss-y? Looks like a gneiss
(Rob) Oh yeah? I wouldn't have pictured that as a gneiss, but I trust your judgement
(David) Looks like it's got foliations in it so, which is a metamorphic texture
(David) that develops, and then the green might be a secondary sort of chlorine
(David) alteration that's happened to it (Rob) Okay
(David) It strikes me as at least metamorphic, if not gneiss, then
(David) something similar.
(Rob) Well I think it's nice either way [laughs]
More interesting mud formations, that must've flipped over, huh?
I don't know if the rocks were on top and came out, or if it flipped up off of a
rock I think. Yeah, I think...I dunno. [laughs]
(David) Huh.
(Rob) Here's some more little kind of cups formed from rocks.
Okay, back to the good stuff.
What you got there?
(David) Well, it looks like some sort of sedimentary rock with a concretion inside
(David) that's a really cool texture, I like the red
(Rob) Yeah, that's an interesting one. I thought it was one of those little ice
formations at first. Cool!
(waves crashing)
This is a different rock I've never seen (David) Yep, I think it's some sort of coral
(David) I don't know if this will show up, but this is all textured, so there's like
(David) the layers going this way, but there's also sort of lines going this way
(David) and it's stippled (Rob) that's neat
(Rob) Check out the green color on that one
It's weird, because the back of the rock is boring, but really nice color there
(David) Yeah
(Rob) What you got there? (David) It's a porphyritic basalt
so, the porphyries would be these lighter colored crystals, they'd be
I forget what type of feldspar, but they're some sort of feldspar
and they crystallize at much hotter temperatures than the surrounding magma
so they crystallize first, and then somehow, the matrix is quenched
So you get these big crystals surrounded by an amorphous, or mostly amorphous
matrix. (Rob) Okay
(Rob) Those are - they always catch my eye when I see them, I see those quite often
a lot of times they're green instead of yellow or orange-ish, like that one.
(David) Yeah, and if uh - if it wasn't quenched, you'd get these big crystals
in a
almost in a gabbro. (Rob) Okay
(David) Just like basalt, but it takes longer for it to crystalize, so instead of
it all being a sort of a matte black, you would see individual crystals, kind of
like granite, like the difference between granite and rhyolite, it's the same
chemical constituents, the same minerals (Rob) okay
but since granite takes longer to cool, those crystals can grow larger.
(Rob) Oh okay. (David) Like rhyolite which is quenched
and can have much smaller crystals. (Rob) Oh, I didn't know the difference.
(Rob) That's an orange quartzite, I think (David) Yup
(Rob) I find that every so often. Sometimes I take those home and cut them up and make
crosses and stuff out of them. They tumble pretty well. Pretty rock.
(David) Reason I think - well, you asked me what I thought it was, and I agreed with
you that it's quartzite. The reason I think so is, it looks as though, and it's kind
of hard to tell, but within - it looks as though the crystals, or the grains that
would have made this up if it were originally a sandstone have grown
and fused together, and that occurs through a process called contact metamorphism
so, if it's contact metamorphism, this would have originally been a sandstone by some
sort of large magma body, or some sort of hot, really hot material that baked
the rock, and kind of like your Christmas cookies, as it bakes, the ingredients expand
and fuse together, and you get something like this, although I wouldn't recommend
eating this. (Rob) [laughs] Maybe a little sour cream
(Rob) Got a puddingstone hiding down here
(David) Nice
(Rob) One [laughs] one little piece
I don't know if that's worth keeping, if I tumble that I'll probably tumble the red
off of it, so I may as well leave it here.
Just walked a couple more steps and found this puddingstone, which I will keep
Kind of a fun stripe in that one.
Sandstone? (David) Yup, just neat colors, sort of a
purple-y maroon (Rob) I think that might be Jacobsville
sandstone, you find that up in the UP a lot, but you don't usually find it here.
David just picked up this coral of some sort, that's neat how you can see
they're all growing upwards, that's neat. (David) Yeah
(Rob) That's a good one! (David) Yeah
(Rob) That's really good
That one goes in the bucket for sure.
That's cool. (David) Yup
(Rob) Brecciated something or other? Definitely
(David) Yep, might be a rhyolite matrix it's kind of hard to tell, but
(Rob) Yeah
Cool looking rock. (David) Yeah
(Rob) Oh, there's a puddingstone
little bit of pudding on the end
ooh, there's a neat one
(David) More of that Jacobsville sandstone? (Rob) No, that's something different.
(Rob) I've tried to tumble this stuff before and it's soft and doesn't tumble
well. But I don't know what that is. (David) Yeah, I guess looking at it closer
(David) It looks much more smooth there than the sandstone would be.
(Rob) I like those whatever they are
(Rob) This is only the second petoskey we've found! It's a pretty nice one though
(David) Yeah!
(Rob) Here's a horn coral
(David) Yup
(Rob) All kinds of fun stuff
Another puddingstone, let me get it between waves here
that's not too bad, but I've got enough for now.
David's finding all the good puddingstones that's a really nice little guy.
Those are - I like the little ones, because you can throw them in a
tumbler. Nice one! (David) Thanks
(Rob) Mudstone, huh? (David) Yeah, so uh, yeah I really like
sort of swirly textures you see, and so this would've probably, the texture
there probably would have formed shortly after this was deposited, so
and it's a mudstone, the mud would've settled out in some sort of lake or
body of water, and then somehow the layers would've slumped
(Rob) Okay (David) And that's what would've formed
these sort of crinkles and waves in it, and then over time it would've been
buried again, and then turned - lithified, turned into a stone
preserving those textures. (Rob) Okay. You know what, I said let's
not take that one home, but maybe we could polish one side of that on the cab
machine
That might be a little project to do later this weekend.
(David) Sure!
(Wheel grinding)
(Rob) You got her all dried off? (David) Yup
(Rob) It's really good. (David) Yeah, I think it turned out pretty
nicely. (Rob) Flip it over just to show the contrast
that's how it looked originally, and there's the shiny spot. Yeah it looks
great. (David) Yeah. It's fun using your new
cabbing machine (Rob) Yeah, it's been a lot of fun.
Alright! Back to the beach.
(waves lapping)
Well, David and I just both found petoskey stones, that's nice looking, but that's
the only part that's petoskey, right? (David) Yeah, looks like the rest of that's
(Rob) Other fossils (David) Yup
(Rob) Cool on that one part. And mine's a really bad one. Really washed out
It's stuck a little It's a pretty color of green with a stripe
Picked up a little charlevoix stone, or favosites
It's huge! Do you need help carrying it home? [laughs]
(David) Maybe [laughs]
(Rob) Just grabbed a decent little petoskey There's not a lot of petoskey stones on
this beach, but there's a few.
Nice little horn coral.
The waves are coming in, there's all these little rocks, we're on our way back
we've already looked this over, but they're moving over pretty quickly, so
just picked that one up, that's probably the best petoskey yet
it's got some black on it, but I don't care. Nice!
So we're going to polish that one up (David) Yup
(Rob) Dip that one in the water just to see how different it looks, just in here's
fine. So that's actually a pretty nice rock. Alright, go to it!
(Wheel grinding)
Hey that turned out great (David) Thanks
(Rob) Yup, nice little petoskey stone. It's fun when they look wet when they're
still dry.
Well I'm catching up with David, that's a pretty nice little puddingstone
Well that was a fun little hunt, remember last year when we found all the floating
snow ball things? (David) Oh yeah, that was a blast
(Rob) If you haven't seen that video I'll link it here, you should go check it out
So uh, merry Christmas, happy New Year, and we'll see you later!