Guess the Cover of American Laboratory—January 2013

Correctly identify this month’s cover image and be entered to win a $10 Amazon gift card (one entry per person; you must be 18 years of age to be eligible. See contest rules at

The subject of this month’s cover image was once used in the production of dyes as well as in the detection of blood. In 2010 it was placed on the EPA’s list of Chemicals of Concern and is now considered to be a carcinogen. The image was captured using polarized light at 250× magnification.

What do you think it is? Enter by leaving your answer in the comments section below. Stay tuned for the answer and for next month’s cover image!