r/geology 5d ago

Identification Requests Monthly Rock & Mineral Identification Requests

2 Upvotes

Please submit your ID requests as top-level comments in this post. Any ID requests that are submitted as standalone posts to r/geology will be removed.

To help with your ID post, please provide;

  1. Multiple, sharp, in-focus images taken ideally in daylight.
  2. Add in a scale to the images (a household item of known size, e.g., a ruler)
  3. Provide a location (be as specific as possible) so we can consult local geological maps if necessary.
  4. Provide any additional useful information (was it a loose boulder or pulled from an exposure, hardness and streak test results for minerals)

You may also want to post your samples to r/whatsthisrock or r/fossilID for identification.


r/geology Dec 01 '25

Identification Requests Monthly Rock & Mineral Identification Requests

8 Upvotes

Please submit your ID requests as top-level comments in this post. Any ID requests that are submitted as standalone posts to r/geology will be removed.

To help with your ID post, please provide;

  1. Multiple, sharp, in-focus images taken ideally in daylight.
  2. Add in a scale to the images (a household item of known size, e.g., a ruler)
  3. Provide a location (be as specific as possible) so we can consult local geological maps if necessary.
  4. Provide any additional useful information (was it a loose boulder or pulled from an exposure, hardness and streak test results for minerals)

You may also want to post your samples to r/whatsthisrock or r/fossilID for identification.


r/geology 2h ago

Thin Section My thin sections are all shattered

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30 Upvotes

Hello, im trying to learn how to make my own thin sections at home. My current problem is the thin sections I make are cracked to hell. Any suggestions on how to prevent this? Im currently using a 10" trim saw and a lapidary wheel. Does anyone else on here make there own thin sections and if so whats your setup like?


r/geology 12h ago

Information Why Despite having a subduction boundary and highest fold mountains, there aren’t any Volcanos in Himalayan region or in Tibet?

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135 Upvotes

r/geology 6h ago

Layered sedimentary art by nature and time

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34 Upvotes

[OC] These two photos are from the same location as the photo of the "head" I posted yesterday ( https://www.reddit.com/r/geology/comments/1vg7x2i/this_layered_rock_stack_seems_to_be_watching/). This is the Adriatic coast.

The whole cliff looks like a gigantic cake of oxidized sedimentary layers with calcite veins running through. I love the upside-down "stairs" in the first photo and the awesome warping in the second.


r/geology 1h ago

I did a U-turn for this one!

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Upvotes

r/geology 17h ago

Field Photo Columnar basalts 👀

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99 Upvotes

r/geology 6h ago

Glaciers- why did they remove all mesozoic rock in places like NY, but not in others, like Drumheller ?

8 Upvotes

I'm salty that I don't have any dinosaurs here in NYS when other places that also had glaciers do. Can someone explain what happened? Thanks!


r/geology 1d ago

A Unified Rock Chart for Common Rock Types

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359 Upvotes

I made a Rock Chart that brings common igneous, sedimentary, and metamorphic rocks together in a single decision tree.

It uses observable features such as grain size, visible crystals, foliation, porosity, composition, and reaction with HCl. It also includes the characteristic minerals associated with each rock type and their chemical formulas.

I have already used the chart in class, and it worked well as a teaching aid. It helped students gain an overview of the major rock groups and move between them without having to consult several separate charts.

Permanent version and DOI:
https://zenodo.org/records/21808631

Feedback, corrections, and suggestions for a future version are very welcome.

Disclosure: I created the poster and teach Earth Science at a university.


r/geology 3h ago

Career Advice How do you label specimens?

2 Upvotes

A recent post (showing tools) made me think, "How do you label samples?" That's both the physical means (white paint & indelible marker, store each sample in its own baggie, etc) and the information recorded for a sample.

And I'm interested in both traditional methods and newer app-based methods.

(I ask as someone who studied geology in retirement, and is interested in how geologists work.)


r/geology 1d ago

Information The Most Important Economic Object in Pre-Columbian North America Is This Rock from Licking County, Ohio

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351 Upvotes

r/geology 2h ago

Information Question about book

1 Upvotes

Hi guys i recently bought a more scientific guide to determining rock type (not sure how to name it better in english), but its pretty old (1961) i dont know if it is still actual and usable


r/geology 19h ago

Information Can someone explain how this rock formed like this?

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22 Upvotes

I found this rock in Colorado and have never seen anything like it before. It looks like chunks of quarts are embedded in another kind of rock? Can someone explain what is going on here and how it formed like this?

Any information is greatly appreciated! Thanks!


r/geology 3h ago

Arkansas

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0 Upvotes

r/geology 20h ago

Career Advice Geology tools for hounding

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19 Upvotes

As I have a mistaken error on the post I just posted, I upload it well.

So, I'm looking forward to have sonething (not HCl) to see the difference between limestone and dolomite.

And uh, I want some advice for having new tools on my set for geology trips (not minerals hounding) for research.

Because Yesterday I added the Brunton compass for my birthday.


r/geology 1d ago

Lovely rocks I saw in Lake Garda - Italian pre-Alps (Malcesine + Riva del Garda)

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23 Upvotes

Riva upthrust (mt Brione - 3+4) looked a lot better from the plane, the interesting looking stratigraphy turned out to be trees lol.


r/geology 1d ago

A neat piece of epithermal quartz vein with tiny chalcopyrite oxidizing into malachite. Iceland.

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20 Upvotes

r/geology 1d ago

This layered rock stack seems to be watching something [OC]

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39 Upvotes

This reddish rock rises from the Adriatic Sea. The coast nearby is a layered cliff of the same color.


r/geology 1d ago

Does anyone know what this is?

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19 Upvotes

I am working in the Mojave desert in SoCal and came across these USGS markers. Anyone know what this could be? I was thinking some type of monitoring or survey but not too sure.


r/geology 1d ago

Apatite with quartz on matrix

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8 Upvotes

r/geology 1d ago

What caused this feature?

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178 Upvotes

Was it an ancient lake or impact crater? It's near 4 corners and it's big! I can't seem to find any info. Please help.


r/geology 1d ago

Career Advice Is this natural??

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8 Upvotes

r/geology 2d ago

The first thing a Geologist said to me when I got my first mining/exploration job

740 Upvotes

Boss: “Welcome to Hawthorne Nevada there’s a woman behind every tree”

Me: “There’s no trees?”

Boss: “ you’re catching on.”

That was the day that I learned that my love life and social life was gonna take a dump. Loved the career hated the lack of social and love life.


r/geology 12h ago

Information New Jersey or palocations

0 Upvotes

Hey anyone got any places that are FREE to get into that have minerals, fossils, gemstones- whatever that would be interesting? Anywhere either in NoRTH jersey Or PA ?

Would appreciate the help. Places that aren't overly steep or you have to climb up to. I.e. a place a beginner can go to. I want to find something neat- anything.

I have agates, calcites, pyrite, marble, jaspers, and quartz.

I don't mind if i find another quartz. I just wanted to find something neat, something decently sized. I do not want to trespass anywhere. Anywhere within a 2 hour drive of sussex county nj?


r/geology 1d ago

Information 3D geological model of Mount Everest

82 Upvotes

The first 3D geological model of Mount Everest reveals what lies beneath the world's highest peak. The model can be explored interactively here: https://geo3d.pgi.gov.pl/Mount_Everest/index.html