Finnish artist Erno-Erik Raitanan has created a visually arresting series of art pieces using a most unusual medium. Can you guess what it is? What if I told you that the name of the series is "Bacteriograms"? Give up? Answers after the jump.

According to Raitanan, the images were created by cultivating bacteria samples on a color negative film. He describes his process, and the motivation behind it:

You'll find more examples of Raitanan's work on his website.
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