"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.  
• You see, each type of pollen looks different when you get up close.
• 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!