The blackboard of the middle ages
A large steel shield in the form of a sea-shell attributed to Athena, the goddess of civilization, craft wisdom and war.
A common mistake when writing adventures set in deserts is to assume that the climate is too ferociously hot to wear armor. Historically, most battles in deserts involved troops dressed in protective armor. Although they would have been miserable during the hottest part of the day or the hottest part of the year, desert weather isn't intolerably hot 24/7.