Are the 2017 Total Eclipse forever stamps still working?

Philatelic Foreword by Jay Bigalke

The eclipse of 2024 is fresh on the minds of all of us in the Sidney, Ohio, Amos Media office. Sidney was within the path of totality along with many of the towns nearby. With the building closed, we had the day off to enjoy the experience, and it was quite an experience.

Mostly sunny and warm skies greeted Ohio at the right time, not the standard spring weather here.

My day started off, naturally, at the post office preparing postcards to send to friends. I still had United States 2017 Total Solar Eclipse commemorative forever stamps (Scott 5211) stockpiled. Knowing this event was coming, I used them to mail the postcards.

Coincidentally, after checking my email, I saw that a reader had a question about the special heat-reactive thermochromic ink used on the 2017 stamps. His message indicated that a finger didn’t work in making the ink warm enough to trigger the reaction.

When the black disc covering the moon is warmed, as from the touch of a finger, the moon on the stamp is revealed. As the stamp cools, the black color returns and the moon is hidden once more. On my stamps, I did notice the effect was not as fast as it was when the stamps were first issued.

At the time the stamps were issued, an article by Charles Snee in Linn’s discussed how exposure to extreme conditions could change the effectiveness of the thermochromic ink. That article pointed out that approximately 84 degrees Fahrenheit seemed to be the magic number for triggering the reaction.

The USPS also sold a black folder for the stamps at the time of issuance meant to increase the life of the thermochromic ink. So, if your stamps have been exposed to light since issuance, the effectiveness of the ink probably is decreasing.

I also noticed that some of my panes, ones that were not pressed flat in a book and just in a glassine, started to exhibit curling.

It was a fun gimmick at the time, and I still think it was the right effect for the stamp. Perhaps a new version for this eclipse would have been fun, with a similar result when exposed to ultraviolet light, like the recent Canada Post Eclipse issue.

Either way, I still had fun sending postcards using the old stamp for the latest eclipse.

Connect with Linn’s Stamp News: 

    Sign up for our newsletter
    Like us on Facebook
    Follow us on Twitter