DMT Polariscopy

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Making a thread to post all the photos and videos that I will be taking. I don't want to overload the server with a seemingly infinite fountain of beautiful alien landscapes so I'll try to focus on just the most captivating visuals. Ever since putting the first slide under the microscope a couple days ago I've been obsessed and fascinated like I'm meeting DMT for the first time again. It's a very cool way to look at the crystal, I highly recommend it. Microscopy and crystallography is just a hobby for me, and I'm a beginner, so I can't yet explain why things look the way they do, beyond some basics.

Microscopes:

Polariscope - A small standalone scope with no magnification. It transmits plane polarized light through a sample. A second polarizer above, called the analyzer, can be rotated. The angle that the analyzer is relative to the polarizer changes which light passes through. When the analyzer is perpendicular to the polarizer, this is called cross polarization. Under cross polarization, all of the transmitted light gets blocked by the analyzer, creating an astonishing effect where a transparent sample appears to be glowing of its own light. For the crystal to glow it must bend some of the polarized light as it travels through the mineral, changing color and brightness depending on the composition and angle of the crystal. Gemologists use these to help distinguish gemstones.

Amscope ME1400T - A reflective light microscope. Instead of transmitting light through the sample, it bounces light off the surface. It's used in metallurgy to inspect the crystal grains within metallic solids, or in petrography to identify mineral grains in thin section. In petrography, a very useful tool is to use polarized light, which creates interference patterns in minerals that indicate how light moves through them, helping to identify them. I bought this scope for petrography, but the application applies well to crystallography. It has a polarizer & analyzer built into it. The photo at the header was taken through the ME1400T.

Amscope SM-1T - A stereo zoom microscope. Basically just a big magnifying glass. Also uses reflected light, but with less magnification. Great for looking at objects larger than a slide, like actual crystals. The polariscope can be placed under the SM-1T to view specimens in polarized light. Below is an image of the same crystal, photographed through the SM-1T + Polariscope.



Camera:

Amscope AF408N - Both microscopes have trinocular ports for the camera that I swap between them. It can transmit a 4K live feed to my TV, which looks amazing in OLED. I haven't figured out how to calculate the magnification through the camera yet, but once I do I will be able to add a scale bar to the photos. It also takes great video. I'm really happy with this camera and being able to share what the microscope reveals.

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Right now it's more of an art form, but I think with enough observation and some informed explanations we could learn a lot from watching DMT grow on a slide. I invite anyone that is more experienced with this to help with that

This video through the SM-1T + Polariscope illustrates what it looks like when rotating the polarizers relative to the sample. When grains go black it's called extinction. When they're colorful it's called birefringence. When shadowy bands of extinction wash over the entire crystal structure, it's called an interference figure. It all has to do with how light slows or splits when traveling through materials. A smarter person could use all this information to determine not only what mineral they're looking at, but also what axis of the crystal structure they're looking down. It apparently could also be used to analyze purity, or polymorphism. As we can see, there are pure solid transparent shards in this sample, that fan out into a wave of less ordered formations.

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I've seen more formations in these slides than I believed DMT could exhibit. I'll introduce more of them as I get time to write amateur descriptions for them. How freakin' psychedelic is polarized light tho?!

 

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Crystals growing on a slide. In the beginning we can see agglomerates of crystals with a bunch of refractive diamonds growing into a matrix. A gas or immiscible liquid gets secreted, I'm not sure from where but seemingly from within the melt. Must be invisible quantities of air or something that got trapped as the crushed solids melted into a liquid. I plan to experiment with crystallizing a slide in a vacuum chamber to see if that makes a difference.


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Here's the wave front of a growing crystal. From the multiple colors it might be considered many crystals, but they're working together to progress the same larger system. Look how it interacts with the bubbles. Individual blades spike forth, pushing the bubble.

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This thing is pretty cool. At the very tip there seems to be pure crystals growing and overlapping. The crystal edge quickly pixelates and becomes less uniform. This might be amorphous microcrystalline DMT, or polymerization, or something else. It seems to be a mix of forms, with a cool dendritic plume formation. Similar to the plumes radiating out from the crystal in post #1, but dirtier looking.


Another amorphous plume I found.

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And a video of that amorphous plume being consumed by a higher order crystal. Unless I'm seeing an overlap, the amorphous formation seems to get re-ordered into the crystal lattice of the growing neighbor. As it does so, gaps are formed, which I interpret as a side effect from less dense to more dense crystal formation.

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Two higher order waves competing over an amorphous field. Sorry about the motion-sensitive auto focus. Notice the outlines of enormous blades within the crystal wave on the right.

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Here we have a growing amorphous field on the right, and a growing crystal field on the left. The bottom of our view is fresh melt and the two fronts are squishing out an air pocket. Above, we can see voids of air that got trapped. Like before, blades are thrusting out of the crystal wave, toward the air. Notice how it has smeared the orderly formation of the crystal wave, making it more colorful where it had been pushing against the bubble. We can also see very fine formations reaching through the air pocket; tendrils with curvature and dendritic branching. At the top, the crystal wave has already bridged across the bubble and re-fans out, consuming the still-growing amorphous wave.

I think that's confirmation that it's not overlapping either, since the air squishing out implies that both sides were totally packed with growth.

 

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We still have more photos of slide formations to review, but I've been looking forward to scoping some actual crystals and finally got some decent ones. A lot actually. I'd like to figure out how to reduce the quantity and increase the size. These are very small right now, about 2mm x 2mm. To the naked eye they all look roughly the same, which makes sense since it's one crystal system, but under the microscope it's like snowflakes - I haven't found two crystals exactly alike yet. And none of them are flawless, which adds to their uniqueness.

Anyway, I was eager to look at them under polarized light, so I've taken video of a few nicer ones to share. Basically just looking at the geometry, which is sometimes hard to discern when the crystal isn't perfect, and is still beyond my understanding anyway. But it might almost be enough to show to a gemologist and have them identify the crystal system by eye. We already know it is monoclinic from a study, but it would be neat to get a blind test confirmation to go with the x-ray math.

And I also wanted to brush up on the basics while pointing out extinction in anisotropic crystals again. You'll see me rotating crystals, which are between two polarizers that are crossed at 90 degrees. Light waves are normally vibrating in random directions, and polarizers filter light so it's only vibrating in one plane, called plane polarized light (PPL). If the second polarizer is perpendicular to the first polarizer, the polarized light exiting the first filter gets blocked by the second filter. This is called cross polarized light (XPL). In this state, all light to the viewer is extinguished and the landscape appears black.

When a transparent object is placed between the crossed polarizers, different things can happen. NaCl, for example, is isotropic. Just like its physical cubic crystal formation, its optical properties are identical on every axis, so light will not bend through table salt no matter which way it's oriented.

Glass doesn't influence the polarity of polarized light waves, so it will match the background and appear black in XPL. Glass is silicon dioxide, basically the same mineral as quartz, just in an amorphous arrangement. You might say glass and quartz are polymorphs of silicon dioxide. Quartz is an anisotropic crystal of SiO2. Optically, anisotropy basically means light passing through the crystal behaves differently depending on the orientation of the crystal relative to the light. In some orientations, the light passes through the crystal unaffected, so in XPL the crystal appears black, and this is called extinction. But when rotated 45 degrees, suddenly the light passing through quartz gets twisted and changes polarity, allowing it to pass the second polarizer in a XPL setup and appear to glow.

DMT is anisotropic, which is the foundation for why it looks so interesting in polarized light. You don't get the birefringence colors in relatively large specimens like this. But we can see the crystals go into extinction every 90 degrees. More or less just a testament to the optical purity of the crystal - proving that the molecules are really all aligned, and that the alignment is anisotropic.

So get in! We're going seed shopping.

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Here's a nice bunch of crystals, each with its own extinction angle.

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And this is a nice prism that a bunch of smaller crystals nucleated on. The stacking of multiple different crystals in the light path causes the anisotropy of each to average out, causing the light to vibrate in many directions again by the time it reaches the second polarizer. So the aggregate of small crystals appear to stay lit while the prism goes extinct.

 

[Ruffles]

Excellent Icon!

Is it freebase?

 

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Excellent Icon!

Is it freebase?

Thanks! Yep, everything in this thread so far has been freebase. I do have some benzoate gems too, haven't looked at them under polarized light yet.

 

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The Garden of Mysteries.​

Here's a bunch of slide formations that are still beyond my understanding at the moment. Photographed through the Amscope ME1400T. I haven't made any new slides recently to try to catch it forming live, but I'll take a wild guess about what's going on. I still hope someday someone who knows better can come through and shed more light.


In this first image, on the left side of the frame is what appears to be an amorphous solidification, and on the right side a more crystalline one. But between the two, several smaller systems grew. Judging by the voids, this might have been an air pocket in the melt or something. Perhaps some melt residue was caught in this pocket and was unable to join either the amorphous or crystalline formations.


In the second image, we get a closer look at the mystery formations. The formations are fragmented, but the fragments all lean in uniform directions relative to other fragments of that formation, indicating one system. The like-colors of the fragments through cross-polarized light also indicate these fragments share one crystal orientation.


We see more of the fragments here, but it almost looks entangled. The rainbow colors are difficult to interpret, but it can happen when a birefringent material exhibits varying thickness, shifting the wavelength refracted. Along the fringes we can see little tails sticking out that are a uniform thickness, orientation and therefore color. The green zones are where it would be most thick, like a topographical map, and descends through the spectrum from green-blue-violet-red-orange, down to the base color. The smooth bullseye transitions in color around the rainbow peaks may suggest the molecules within the peaks are still in alignment with the valley formations, despite the color gradient. In contrast, zones where it is browning might also represent areas of thickness, except by separately oriented formations overlapping, mixing and muddying their birefringence colors. My gut wants to say "Polymer", but that's just speculation.


A dirty crystalline wave on the left shot spires out of its front, piercing into a polymer pocket. The spires seem to have re-ordered the polymer material into a fragmented, yet uniform orientation relative to the crystalline wave.


A polymer pocket tucked within a crystal wave. This might have started as a pocket of melt material that was too polymerized to join the surrounding formation, so it got condensed until it self-solidified. Notice the intriguing thread-like formations within the smaller shapes. Also notice how the colors are not all uniform, some fragments are in isolated orientations relative to the majority.


Another mix of formations that blurs my understanding. Amorphous, polymer, liquid crystals, plumes of crystalline overwriting amorphous, who knows what's going on.


This shot is a little bland, but the uniform gaps between formations are also a mystery. Reminder, this stuff grew out of a melt. How does it know when to partition? It's as if the different types repel each other. Notice how the spherulite on the left has a thin layer along the edge that grew against the grain? Very peculiar.


Here is another mystery partition, between spherulites. I did not draw this or put something on the slide to make this. As far as I know, it's a natural formation. It looks like it cuts through the spherulite, so it must have happened after the growth occurred. This is sealed between two slides of glass, no air exposure. Maybe a mud crack as the spherulite dried? It's so linear though, as if it's tracing cleavage planes. Dmt plate tectonics? Entity crop circles?


This is a really cool shot IMO. There's a ribbon of liquid crystal fragments, but they alternate orientations. When leaning bottom-right, the fragments are turquoise; when leaning down, black; bottom-left, mauve. How in the heck does that happen?


And I saved the best for last. Not even gonna try to describe; a picture's worth a thousand words.

Forbidden Fruit in the Garden of Mysteries.​