An ancient Egyptian mummy was wrapped in an unusual mud shell
The technique may have been used to repair damage or mimic royal burial customs

CT scans of an ancient Egyptian mummy (pictured, with the coffin it was inside when purchased by a collector in the 1850s) reveal that under its linen wrappings, the body is encased in a shell of mud.
K. Sowada et al/PLOS ONE 2021 (CC BY 4.0)