Small snowflake, around 2 millimeters in diameter (companion crystal proportionally smaller). 8 shots averaged to boost signal-to-noise ratio. Glass background with backlight, additional lens Helios 44M-5, december 2012, Moscow. Better viewed in original resolution: 1200 x 900 pixels.
If you want to see more snowflakes, you can browse through all snowflake pictures.
Here you'll find snowflake photo wallpapers in numerous resolutions and screen proportions, up to Ultra HD 4K.
And here is article about snowflake macro photography.