Hey y'all,
Happened across this Vatican pen that was up for sale. I'm not sure what the make is and was pretty unsuccessful with a Google search. So far I found the following: the inscription is in latin and roughly translated says "he/she signs everyone his due" or "law gives everyone his due". This quote is one out of four other inscriptions on the ceiling of the Stanza della Segnatura (and a quartet of medallions). The "stanza" is part of four Raphael rooms in the public part of apartments in the Palace of the Vatican. :)
Hoping the folks here can help! Thanks in advance :)
Images here: https://imgur.com/gallery/6ExYSHI