86 DOS Version 0.1 C Serial # 11 (ORIGINAL DISK) (archive.org) This is the precursor to MS-DOS and is likely the oldest known version to survive. (I had previously uploaded Version 0.34, which was at the time thought to hold that honor.)
Garnet (Wikipedia) Garnets ( /ˈɡɑːrnɪt/) are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives.