A palimpsest is a manuscript page, from which the original text has been scraped or washed off, so that the page could be reused for another document. Gabriele and Gerald used the form for a combination of watercolor and ink with asemic writing; i.e., without semantic content. You can find examples in works of Paul Klee, Joan Miró, Rashid Koraichi, Cy Twombly and others.
Finally, the postcard was sent to Mikel Untzilla.