MICRO-CRYSTALS IN POLARIZED LIGHT, AND HOW TO GROW THEM

by Loes Modderman, The Netherlands

 

 

To most microscopists this is a rather unknown technique. When you try it, you'll see it isn't difficult, and very rewarding. All you need is a set of polarization filters (which come in handy anyway for biological purposes), and some household chemicals to start with, like fertilizers, soda, soaps, decalcifiers, and sweeteners. There are many more. When you get the hang of it, you'll find that almost every chemical crystallizes one way or another.

This is how it goes:

Dissolve a little bit of the chemical in water. In most cases water is fine, but sometimes alcohol or another solvent is needed. The solution doesn't have to be saturated. Test-tubes are excellent for this purpose; when properly closed you can store them and use the solution again. Next: spread a few drops on your slide. When your slides are cleaned with water and soap, surface-tension will be reduced, and you can use the total surface of your slide. I never use cover slips myself, but that's up to you. When your slide is ready, pick it up with a pair of tweezers, because you are going to heat it. For this purpose a night light (small candle) will do nicely. Keep your slide moving, or it will crack. When the water starts evaporating, crystals will appear. If they don't, try cooling and heating again, speak to them, blow a little if you must, and if nothing works just lay the slide on a dustfree surface and wait an hour. Many times, when you pick up such a hopeless slide again, lo and behold, there are crystals all over it.

Tiny crystals on your slide don't look like crystals at all. But wait and see what happens under the microscope. In polarized light an abundance of beautiful and intricate vistas will appear, sometimes in dazzling colors. With a little luck you can observe the crystals growing, which continues under your microscope for a while, because of the heat of the illumination. Some crystals take their time, but some grow very fast, and are not easy to catch. To enhance and differentiate the colors, it is helpful to use a piece of plastic on your polarizer.

Some experience is needed to make the most of this technique, but that goes for everything. When the content of your kitchen cupboard is crystallized, you can try other stuff. Every drugstore has a rich and inexpensive supply . Pharmacies can provide paracetamol, ascorbic acid (vitamin C) or acetylsalicylic acid (aspirin) and many more. Pills don't work well, the pure stuff is much better. Not all chemicals need heating. Sometimes you can simply put them away and they will be crystallized after some time. It happens that the crystallization process goes on for days or even months, so it can be a good idea to go through your crystal collection once in a while.

Melting is another option to obtain crystals. For some chemicals that works very well, but others are likely to burn. Many chemicals are easily mixed on your slide, and combinations often give great results. But remember: crystallization is a wonderful but very unpredictable phenomenon. You never get the same result twice. Sometimes a miracle happens, but only once, try as you might. There is one consolation: another miracle will happen soon enough.

The pictures are made with an Olympus OM2 camera . Magnifications are low, mostly with objectives 5x and 10x. That makes a stereomicroscope a very suitable instrument for this technique too. I always use normal daylight films, 100 ASA, with a compensating blue filter in the condenser of the microscope. If you have questions, please don't hesitate to ask them.

Good luck!

Loes Modderman E-mail: Science_art@wish.net

Editor's note: The images shown below are a selection which Loes has kindly shared on Micscape. The author has an extensive and stunning selection of crystal images and derived artwork on her web site 'www.ScienceArt.nl'. Please contact the author if interested in their use.

Related links: The basic principles of using crossed polarising filters are described in this Micscape article.

 

 

'Winter Wonderland' Crystal Gallery
All taken between crossed polarising filters.

The author's image codes are included, and should be used if referring to
specific images when contacting the author.

Borax, arginine and hydroquinone.  Just a lucky mixture. The sharp lines are typically borax. Magnification about 50x.  

Image 793-27 

 

 

Glycine and dextrin.  Glycine is  very rewarding  stuff; it curls. Dextrin has the effect of smoothing things up a bit. Their cooperation leads to beautiful plant-like structures (this time). The gold comes from removing the blue filter. Magnification about 80x.  

Image 696-03

Decalcifyer for your coffee  machine.  Bought on one of my tours through a drugstore.  Slide left to crystallize by itself, and almost forgot about it.  Surprise! These organpipes are a personal favorite. Magnification:  50x.  

Image 660-32

 

 

Soda and hydroquinone.  Hydroquinone is a wonderful chemical, though toxic.  When other chemicals refuse to crystallize, an added drop of hydrochinon  sometimes  works  miracles. Soda is beautiful too, very easy to crystallize and always near at hand. Magnification: 50x.

Image 716-00

Sodium bicarbonate in gelatineSome chemicals are very nice when you try crystallizing them in a gel. Gelatine, dissolved in hot water to which the chemical is added, works well. But other gels, like hairgel  or silica-gel  are possible too.  No heating, just put it away. These beautiful dendrite forms are reminiscent of trees laden with snow. Magnification: 50x.    

Image 503-11

 

 

ResorcinolOne of the best, and always produces nice and very recognizable crystals.  Their sharp form makes it easy to visualize well known things, like this wintery landscape. Magnification: 50x.    

Image 712-23

Prednisone, vitamin B1 and urea.  If a title was required for this one, it would be: Snowfall at Sunset. Or something like that. The snowflakes are created by the  vitamin B1. Urea is wonderful stuff, and easy to combine with almost everything. Magnification about 80x.

Image 843-08

     Images by and Loes Modderman.

 

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