The crystal has a geometric centre and surprisingly rough ends. Under a microscope, snow can look much less like a neat paper cut-out and much more like an object with a weather history written across its surface.
A crystal can collect droplets as it travels
Riming happens when supercooled liquid droplets meet an ice crystal and freeze onto it. The deposits alter the original outline. If the coating becomes extensive enough to obscure that outline, the resulting snow particle can be described as graupel, a compact pellet formed as droplets build up around the crystal.
The original microscopy-image record provides context for the capped-column form. A dramatic “50,000 times” claim is less useful than the source’s scale information, especially when an image is resized for a screen.
Ice grows through more than one process
Compare the droplet deposits with the larger patterns in a rime-coated forest. For another example of supercooled liquid becoming ice, explore the instant-ice demonstration. Similar words describe related ideas, but the size and setting of the process matter.
Reading the scale of a snow-crystal image
A capped column has an underlying geometric form, while frozen droplets can add a rough surface around it. The contrast between those two kinds of structure explains why the microscopic image looks less like a familiar paper snowflake. The roughness is part of the particle’s subsequent growth.
The source image is more informative when viewed as a record with a scale, rather than as a picture made impressive by a large magnification number. Resizing it on a phone or computer changes its displayed size without changing the crystal that was photographed. Look first for the underlying capped-column shape, then for the rough deposits around it. That order separates the crystal’s basic form from later additions and makes the image useful as an observation of snow growth, not merely an unusual-looking object.
Sources, photography and further reading
Original feature and image attributions:
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