COLORADO SPRINGS, Colo. – A Colorado company is behind a clever color-changing postage stamp that commemorates next week’s total solar eclipse.

Chromatic Technologies Inc. in Colorado Springs created the special ink that changes color depending on the temperature.

The stamp features an image of the eclipse – a black circle with the rays of the sun shining from behind it. Place a finger over the stamp to warm it up and the stamp shows the face of the moon.

Chromatic Technologies said the ink is formulated to become transparent at 84 degrees Fahrenheit. Once it cools to 77 degrees, the ink reverts to black. 

This is the first time the United States Postal Service has used thermochromic ink on a postage stamp.

Chromatic Technologies has used the same kind of ink on products like Coors Light’s color-changing beer cans and Lay’s chip bags that change when exposed to sunlight.

The color-changing eclipse stamps went on sale June 20 and are available for purchase online. A sheet of 16 Forever stamps costs $7.84.