Friday, June 17, 2011

"What the...?" Part 2; How to identify a mystery substance.

Hey guys,
Where did we leave off? Oh yeah, there were two "mysteries of nature" that I was trying to solve:
  1. A yellow flour-like powder veins in the clay; and a 
  2. Very thin white crystalline crust on the soil surface.  
So I sampled them both.
Freestyle soil sampling.

Here is Mystery #1 in the field.  See the yellow powder, look how fine it is.  Can you see it spread on my fingers?

Here is Mystery #1 by microscope magnification. I think it is pollen!
They appear circular, but I can't quite tell due to their small size.
I'm gonna try and get some mineral oil magnification soon.

Here is Mystery #2 in the field.  To obtain the crystalline crust,  I dug out a chunk, which revealed fresh clay (you see the yellow veins, Mystery #1, very clearly).  The rest has that thin layer of white crystal crust on it.
Here, I'll "magnify" again, using my special magnifying lens.

Here is Mystery #2 magnified under the microscope and at various angles.

Thank you Eastside Memorial Green Tech and Mr. Moldenhauer for hosting my curiosity! 
Here are my future plans (if I can acquire a few supplies with limited effort on my part, ahem):
  • Mystery #1 (yellow "flour" powder): Access a microscope with greater magnification and hopefully identify the pollen.  
  • Mystery #2 (tiny white crystalline crust): Attempt to dissolve the crystals in water.  Then, add acetone to see if there is any precipitation reactions. 
    • Why? I'm testing to see if it is gypsum.  I think it is gypsum because gypsum is a very common white evaporite. Also, the presence of gypsum indicates arid environments (like where I was standing at the time).

UPDATE: I haven't found a higher resolution microscope yet.  Also, I tried the acetone experiment, but I don't believe I had enough crystal sample to get significant results; it's a very thin layer.  Alas, the mystery continues... 

Have a great weekend, everyone!


  1. very cool investigative work! keep it up, curious to see what the yellow stuff is. to me it looks like elemental sulfur... which would be pretty cool if it's surrounded by the oxidized form of sulfur in the form of calcium sulfate (gypsum). That would indicate these yellow pockets are formed in the absence of oxygen, by organisms that gained energy by using sulfate (rather than oxygen) as their energy source. Try sticking it in an air-tight jar with some soil and see if it smells like rotten eggs (H2S) after a few days :)
    Have fun!

  2. OMG such great comments! I wish I could drag you with me to the mystery soil. Maybe next time you are in TX! It totally looks like sulfur, but I stuck my nose up in it pretty close (and maybe I licked it for fun) and didn't smell anything. I do have a jar of it in my car that is probably air-tight. I'll go inhale. Thanks!!

    Also, pine pollen looks like Mickey Mouse and this yellow stuff was in a pine forest. I looked for Mickey Mouse shapes under the micro but never saw any- tiny, tiny circles as far as I can tell. I should mail you some !!! ;-)

    UPDATE: If there is a sulfur smell in the jar, I can't detect it. Wouldn't those guys be in very wet (anaerobic) soils? We're arid here. There is a lake very nearby, but I don't think there is a hydro' connection.


  3. did you add water to the soil-powder mix? you might want to submerge some in the water and wait a week or 2 with the lid closed.

    though if it's in an arid pine forest, I'm not sure you would get much elemental sulfur - unless it was a more permanent stream bed at some point.

    otherwise I got no clue! I'm more of a microbiologist than a geologist :)

    happy digging!

  4. It seems to look like Gypsum as seen in the images. But is the surrounding having salty water. Isn't gypsum found in salty atmosphere?