What's On My Slide?

It's that time of the week again!

Time to squint your eyes and look through the eyepiece of that RM11,800 microscope (yes, there IS a price tag on the microscope! Hahaa.) and start analyzing those tiny sedimentary/ igneous/ metamorphic fragments.

Today, my class had 3 hours of Sediment Petrology and we had to observe a gazillion slides to acquaint ourselves with the many particles that make up sedimentary rocks.

How do you know what is what though? Things can be a little confusing, so here's a quick guide to identifying that mysterious particle you've been staring at for the past 15 minutes. (:

#1: READ THE LABEL

If the label says that it is limestone with trilobites, it would most probably be limestone... with trilobites in it. Problem solved!

See this?

The label says : BATU KAPUR TRILOBIT
So, basically - it is limestone.
With trilobites!

See that squiggly line in the middle?
That, my dear, is a trilobite.
Uh-huh. (:

#2: KNOW THY FOSSILS!

Pay attention to your Palaeontology lessons!

If you can't tell the difference between a hand specimen of a brachiopod and a bivalve - how do you expect to tell which is which under the microscope?

Fossils under the microscope - microfossils, if you will - are pretty much the same as their bigger counterparts. Let's test your Palaeontology skills a little, shall we? I'll give you a term. See what crosses your mind when you read it. (:

PELECYPODA.

If you had to Google that up, then maybe you should dig up those old Palaeontology notes right now.

Pelecypods are really... bivalves. Same animal, different name. Gotcha! :D

So what do Pelecypods (Bivalves, if that's what you prefer) look like under the microscope?

They look exactly like their bigger counterparts, just smaller!
See those white crescents?
Those are the valves, scattered all over the slide. (:

#3: KEEP A REFERENCE

Sketch. Take pictures. Anything. Just to keep track of what is what. Make sure you keep everything neat and labelled! Whenever in doubt, check your textbooks or refer to your lecturer. (:

Here are a few other specimens I managed to snap.

BATU KAPUR GASTROPOD

Under PPL
Can you see the different cross-sections of the gastropods?  (:

Under XPL
The chambers are filled with the same material outside the gastropods.
What could it be? Hmmm.

BATU KAPUR ALGA

The big lumps with rings are algae!

The one in the middle kinda looks like a face! :D
The one in the middle is a fossil of some sort, filled in by sparry calcite.
TOP : PPL
BOTTOM : XPL

BATU KAPUR OOLITOS
(Oolitic Limestone)

Lots and lots of Ooids!

Here's a close-up.
You can see the concentric circles of calcite surrounding each nucleus.

BATU KAPUR KRINOID

I suppose the one in the middle is part of a crinoid stem...

And this must be the crinoid's calyx, perhaps?

BATU KAPUR KARANG

Sparry calcite in between coral theca.
Theca... that's what it's called right?
Hahaaa.
*time to dig up Palaeontology notes*

Yes, things can get a little confusing in the middle of any Petrology class. Just have fun exploring and don't ever be afraid to ask. Remember to take a break from staring into the microscope every once in a while so you don't get a headache! (:

Until next time, everyone!

xx

[All pictures are my own, captured using my IXUS130.]