Tanaqui Weaver, cited here recently, reports:
the UK issued a neat 2nd-class stamp with an atom of c60 illustrated. It’s thermochromic black, and a hot thumb on the stamp whitens it out to reveal a captive atom of carbon in the centre. pretty.
Tanaqui Weaver, cited here recently, reports:
the UK issued a neat 2nd-class stamp with an atom of c60 illustrated. It’s thermochromic black, and a hot thumb on the stamp whitens it out to reveal a captive atom of carbon in the centre. pretty.