Skepticism

More Pretty Rock Photos

Since some of you seemed to like these, I thought I would post a few more pretty rock photos with short descriptions. Most of these have the shiny dime as well.

I emailed these photos to myself from the lab computer using Gmail. As a result, my Gmail account was shut down for 2 hours due to suspicious activity. Apparently, sending many high-resolution photos of rocks to yourself is not normal activity. I’d argue that it is a normal activity for me… but I can see how it might be considered spam by some people…

I certainly find these rocks (and many others) beautiful. As the wonderful “First Aid Kit” song posted by Rebecca says, “It’s One Life, and It’s This Life, and It’s Beautiful.” For my one life, this life, I find rocks such as these beautiful. I find many rocks beautiful, but that’s just me. It’s not just rocks. We all can find beauty in one life, this life- be it a sunset, an orchid, a child, a kitten, or a stream of bubbles in beer– there is beauty in abundance everywhere.


Layered travertine with (highly altered) peridotite inclusions.


Layered travertine with (highly altered) peridotite inclusions.


Layered travertine with (highly altered) peridotite inclusions.


Unidentified (yet) carbonate coating on altered peridotite. The carbonate has botryoidal (bunch-of-grape-like!) texture.


Rock “50C” on the outside. Some kind of carbonate and altered peridotite, but the minerals need to be identified. You can see my less-attractive (than the dime) ruler scale here.


Rock “50C” on the inside. Cut slabs reveal much about the inner (generally less-weathered and less-oxidized) portion of a rock. For many rocks, it is impossible to make an identification without breaking off a fresh surface or using a saw to cut a fresh surface.


A close-up of rock “50C.”


Carbonate vein. Dirty brown on the outside, pristine white on the inside. The rock is white where it was broken off with a hammer. A cut slab would be perfectly white, except for the outside edges.


Another carbonate vein.


Close-up of a carbonate vein. Note that there is more botryoidal texture here.

Added for MarlowePI:

When I say that the peridotite has been altered, I mean that it has been changed from its original composition and form. Peridotite is an igneous rock, which means that it is formed from liquid magma. Initially, the crystals found in peridotite– mostly bright green olivine and green and yellow pyroxenes– are bright and sparkly. Over time, the crystals in peridotite both alter (change chemical composition) and weather (physically break down) as they interact with their environment- water, air, heat, etc.

Fresh peridotite looks like this:

Fresh peridotite contains very beautiful green olivines- this is where the gem peridot comes from. Note that the two above photos were stolen from the interwebs. I study how peridotite alters, so my samples never have fresh olivine. I am lucky if I find somewhat fresh pyroxene.

The altered peridotites I work on look like this:

Not quite as pretty, are they? :-)

Evelyn

Evelyn is a geologist, writer, traveler, and skeptic residing in Cape Town, South Africa with frequent trips back to the US for work. She has two adorable cats; enjoys hiking, rock climbing, and kayaking; and has a very large rock collection. You can follow her on twitter @GeoEvelyn. She also writes a geology blog called Georneys.

Related Articles

8 Comments

  1. OK, apparently I didn’t eat enough dessert tonight, since most of thes pictures made me think of candy. The layered travertine totally looks like some kind of nougat.

    Excuse me while I go raid the fridge!

  2. The one at the bottom looks like yogurt and granola. The rest don’t really look like anything but rocks to me.

    Beautiful photographs. You should put the rocks in outfits and call it, ‘America’s Next Top Rock Model.’ It will be a smash hit. I don’t know why but I’m obsessed with non-human things wearing human clothing. I’ve been drawing ravens wearing top hats and bow ties.

  3. I love learning about things I do not know well. Thank you , Evelyn. Your posts are like reading Scientific American.

    P.S. I love Scientific American!

  4. Is the botryoidal texture caused by deposition from a saturated solution? I have troubles thinking of any other physical process which would do this.

    You can check colour calibration in the photos with the ruler, but not the ones with the dime. Wouldn’t it be better to have some rainbow coloured object instead of the dime?

    Do you carry a rock saw (and possibly polishing equipment) in the field, or do you have to be back in a lab for the cut-away photos?

    How many of your samples come back home as rocks, compared to how many come back just as photos? Do geology departments around the world have basements stuffed full of boxes of rock samples that nobody’s looked at for decades? Are they ever thankful they’ve got a decades-old sample to hand which they can readily find in a well organized rock library?

    Do you give leftover cut-and-polished rocks as presents to friends and family? (For a while, I reused my hand-drawn scientific diagrams and calculations as wrapping paper, making sure to reuse pages as much as possible in as many colours as possible.)

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Back to top button