Ice crystals under the microscope

Few sights are as lovely as a snowfall. Except, of course, a snow crystal seen under the microscope.

What first appears to be a mound of featureless white is actually an immense collection of some of the most intricate marvels that nature has to offer.

To get a close-up look at winter’s own art gallery, the only entry fee is your trusty microscope.

What type of microscope is best for viewing ice crystals?

You don’t need fancy equipment to get a good look at ice crystals.

You can use your stereo (or dissecting) microscope or your compound microscope. Or even a magnifying glass at a pinch.

Setting up

Getting snow or ice crystals under your microscope can be tricky. After all, ice (ahem) melts!

Here are some (relatively) quick and easy methods of inspection that have one thing in common ­– all equipment must be kept cold. 

Outdoors

Wrap up warm, grab your microscope and head out into the snow.

You’ll need:

• an outdoorsy/portable microscope
• glass slides (for compound microscopes) or some dark coloured paper/cardboard (for stereo microscopes)
• a thin brush or tweezers
• somewhere sheltered to park your microscope

And, of course, a snowy day.

1. Let all your collecting gear cool down outside (or inside in the freezer compartment of your fridge). Ice crystals are so thin that they’ll melt instantly at room temperature, so everything around them has to be nice and cold.
2. Catch your snowflakes. Grab your now-cold glass slides or paper and set them down under freefalling snowflakes. Or, if you prefer the thrill of the hunt, catch one directly as it falls.
3. Then simply place your snowy slide (or paper) under your microscope and observe. Use your brush or tweezers to collect or arrange the different ice crystals for a better view.

Indoors

If you prefer to be warm while you work, or simply can’t take your microscope outside, here are some tricks that will still give you the ice crystal experience.

You’ll need:

• your microscope
• glass slides
• clear nail polish or hair spray

And, of course, a snowy day.

1. Cool your slides and nail polish (or hairspray). You can put them outside or just in the freezer for a while.
2. Cover your cold slides with a thin layer of cold nail polish or spray your cold slides with hairspray.
3. Place your slides (sticky side up) outside where they can catch the falling snow.
4. Once your slides have trapped a few snowflakes, place them in a box and leave them in a cold place for a few hours. This will allow the spray to dry as the water in the snowflake melts and disappears. 
5. Observe your slide under the microscope. The ice will have left perfect impressions in the nail polish (or spray), leaving you with a dazzling display that you can inspect in the comfort of your own home.

What will I see?

What you won’t see is a lot of colour. While snow appears to be a solid white colour, your microscope will show you that it’s actually translucent.

Snow appears white as it falls and accumulates on the ground, but pure ice crystals are clear. The crystals scatter and reflect the light spectrum, which ends up producing white light.

Ice crystal viewed under a Dark Field Microscope

When it comes to shape, snowflakes are renowned for appearing to have 6 sides. And you’ll find this is almost always true.

This phenomenon is due to the nature of how water freezes. As water turns to ice, the molecules form a hexagonal lattice. Other water molecules then branch off these 6 sides to produce the star shape you’re familiar with.  

Even with the shared pattern of 6 sides, ice crystals come in a truly astonishing variety. From stars and plates to branching trees and triangles, you’ll soon understand why people have come to believe ‘no two snowflakes are alike’.